67 C10 lwb to K10 swb conversion project

[68 TT]

This project started out as a CL search for a set of more daily driver friendly geared axles for my 78 K20 that had 5.13 gears installed by the original owner.

What I ended up with was a 74 K10 rolling chassis with cab and an 84 K5 roller. Both bodies were gutted & very rough and the K10 was very cancered out but I now have two 4x4 chassis and two sets of axles with brakes and two sets of wheels & tires.

After considering repairing the rust on the 74 cab and building up another 4x4 truck rather than completely tearing down my 78 and making it into something completely different than it came from the factory I decided I should resurrect my old 67 C10 lwb truck as a 4x4 and convert it to a short bed while I was at it.

The 67 C10 got 90% turned into a truck bed trailer a few years ago but I never finished the job as life got in the way and I needed to buy a bigger MIG welder to do it right. I did not get rid of any of the other parts from the 67 C10 purely for the lack of time to sort through it all and figure out what was worth trying to sell off.

As a 2-wd vehicle the 67 C10 is pretty worthless half the year where I live due to the fact that the county has only plowed our street three times in the past 20 years and you have to climb a steep grade up to a stop sign just to get out of my neighborhood.

I have seen a few 67-72 trucks put onto square body 4x4 frames before so it was a pretty easy decision to take my complete 67 C10 lwb truck and put the body onto one of the square body 4x4 chassis.

My first instinct was to put it onto the K5 chassis and make it an ultra short bed truck but the K5 chassis is too different from a truck chassis and it would require a substantial body lift just to get the bed on.

Here is what I started with.

[68 TT]

The first thing that needed addressed was to get the rusty cab off of the K10 frame so out came the cutting tools and off it came in pieces. I kept any parts that looked like I could use them on the 67 to repair any damage or retrofit square body components with. Made a trip to the recycle center with a full bed of scrap metal.

Pulled the Dana-44 out of the K5 (that the PO took out of the K10 and put into the K5) and put it into the K10 chassis.

Cut the double length welded together front shackles apart and made one good stock set, installed the correct U-bolt plate on the driver side and installed the K5 front sway bar.

Put the rear springs on the K10 chassis back together with parts from the K5 then bolted up the 12-bolt so it is now a roller again.

[68 TT]

Had a few minutes to work on the project Sunday morning so I cut off the square body rear cab mounts as they are on the wrong side of the frame to use with the 67 cab. Pulled off the saddle tank and the brackets left on the driver side and removed an unused exhaust hanger.

I test fit the K5 fuel tank and had to remove the brake line bracket and the rear crossmember for it to fit. There is a rail road track fabricated trailer hitch welded to the back of the K10 frame rails so it held the rails in place right where they belong.

I will cut up the K5 frame and pull out the rear frame section to get the fuel tank mount crossmembers and possibly the rear bumper mounts. This should fix the damage caused to the rear of the K10 frame when a PO welded the rail road track hitch to it. These parts will get fit up to the frame after the 67 body is fit to the 74 K10 frame as I may have to modify them and their locations to fit the needed fuel tank position and bumper placement.

[68 TT]

The next project will be fitting the cab, front clip and bed to the 74 K10 chassis.

With the bed and cab all lined up properly and the wheels centered in the wells I can fabricate the cab & core support mount brackets and space the bed mounts off the frame as needed to match.

With the square body frame the straight area to shorten to make it a short bed wheel base is behind the rear cab mount so the cab and front clip can stay in place for mock up of the drivetrain.

Once the cab and front clip are in place I will finish the roller cam conversion to the 88 TBI 350 that will be going into the truck. After that is done and I get the engine cleaned up and put back together I will bolt it to the 4L60E and NP208 I have for it & install them. I also have the transfer case crossmember and matching front driveshaft from the square body that the NP208 came from so they will just bolt right into the 74 chassis.

If the trans and/or transfer case hit the low hump on the 67 cab I will graft in the high hump tunnel from the K5 to give me the added clearance. I may just do this anyway to repair the hacked up tunnel in the 67 cab that a PO butchered to use a cheapo direct mount floor shifter. I may be able to salvage some other floor parts from the K5 to repair some other rusty or damaged areas on the floor of the 67 cab too.

After the drivetrain has been fit to the chassis I will cut down the 67 long bed box to make it the short bed length then cut down the 74 K10 frame to place the cab to bed gap where I want it to be. The square body wheel base is a little longer than the 67-72 so I have some room to play here even if I decide to keep the truck a long bed.

The next task at hand will be to get the TBI 350 & 4L60E plumbed, wired up and running.

I want to work all the bugs out of the chassis swap and drivetrain swap before I do any clean up of the body or chassis so I may drive it for a while as assembled to sort things out then tear it apart next summer (when I can drive one of my cars) to paint the chassis and give the truck a paint job & restore the interior.

[68 TT]

I have several square body optical VSS cable driven speedometers so I am going to retrofit a 67-72 speedo face with the square body TBI friendly mechanicals. This way I keep the looks of the stock dash but get the VSS info I need for the TBI system to function properly too.

I will re-gear the transfer case speedo gears to calibrate the output to match the 100 mph range of the 67 speedo and the height of the tires I will be running once it is on the road.

[68 TT]

I have a spare set of square body power window / power lock doors that I am considering cutting up to use to convert the 67 doors to power windows & locks.

The doors are similar in size with similar glass heights so I think this will be fairly straight forward fabrication to make the newer regulator assembly fit the older doors. I may buy a spare 67-72 door from the wrecking yard to experiment on for this.

The latch may take some monkeying around with the rods to get the power lock assembly functional but it should be pretty simple.

Anybody try this before?

I am probably going to retrofit a newer square body blade fuse type TBI vehicle under dash wire harness so powering up the windows & locks will be easy and all the circuits for the TBI system will be present too.

[68 TT]

I got some time to tinker on the K10 conversion today. Got the bed unbolted from the C10 truck arm rear frame section. Only broke two of the six carriage bolts. Not too bad for 43 years in place.

The bed fits the square body K10 chassis pretty well. Using the rear mount holes and centering the carriage bolts in them places the wheels just about perfectly in the 67 bed wheel arches.

Had to drill new holes for the front bed mount points as they were slightly rearward and outboard of the square body bed mount holes in the frame.

The problem area I saw earlier was not too bad. The square body frame slopes downward behind the rear axle further back than the 67-72 frame does. It will only require a 1/4" spacer on the bed mount points to lift the bed clear of the frame transition area.

With a little luck I might get the cab set in place tomorrow so I can get some measurements to fab up the cab mount brackets to align the cab with the bed and center the front wheel arches on the tires.

[68 TT]

Got the cab and front clip onto the K10 chassis and positioned the front wheels centered in the wheel arches of the fenders. This places the front cab mounts 3" forward of the square body cab mount points so the square body cab mounts all need to come off to make room for new cab mounts. The rear cab mount point is right at where the frame starts to step down from the bed area.

Without some minor frame notches it would require a 3" body lift on the bed to get the body lines to line up. I am considering stretching the frame under the cab to move the rear cab mount into the area where the frame is lower before it slopes up to the bed mount area.

I like the height the bed sits now with no lift so I am going to look into what I need to do to lower the cab as much as is feasible to limit the body lift.

To keep it a long bed I would need to shorten the wheel base by 4" so if I still end up doing the short bed conversion I will take 16" out of the straight section of the frame that is under the bed in front of the leaf spring hanger. Plenty of room to do that.

The next step is to get the truck into my driveway, on jack stands and level out the frame rails so I can make sure everything is true and level before I fabricate any frame mounts for the cab or notch the frame for the rear cab mount clearance.

I need to get the K5 shell off the frame and see if maybe the K5 front section will work better for a lower cab position.

[68 TT]

I got a few minutes to work on the frame modifications today. Got the cab & bed back off the K10 frame and set them out of the way. I then measured how much I would need to stretch the under cab area of the frame to make the cab sit the 1-3/4" lower it needs to line up with the bed. Turns out 9" would do it so I marked up the frame to take out 10" for a little wiggle room.

I also marked up the frame rails under the bed to see if there was room to cut it down by 4" to correct the wheel base, the 10" to align the cab properly and the 12" it would need removed to make it a short bed. It is a little tight but it can work.

I cut the 4" section out to correct the wheel base then cut the 10" section out from under the bed and moved it to the area under the cab to relocate the sloped transition area of the frame rearward to clear the cab.

I got it all aligned and tacked together with my flux core MIG but ran out of time to do the joint bevel work and finish welding with the TIG.

I should be able to get the TIG work done tomorrow or Monday with a little luck. I would love to get the bed & cab set back in place so I can start fabricating the custom cab mount stands.

[68 TT]

A few more of the tacked together altered wheel base and modified square body K10 frame.

[Rob H.]

Thought I'd post here, looking good wanting to do this same swap myself. Been getting some ideas together and trying to do all the planning ahead of time. I'm hoping to get started on it later this year.

[68 TT]

Originally Posted by Rob H.

Thought I'd post here, looking good wanting to do this same swap myself. Been getting some ideas together and trying to do all the planning ahead of time. I'm hoping to get started on it later this year.

Thanks, it is coming along pretty well. Slow going as I am very busy with work and my two little girls but I am making progress.

I would definitely get a complete square body 4x4 chassis to do the conversion. It has made the process so straight forward and you can get one pretty cheap too. I got two for only $300.

[Rob H.]

Well that's alot of the reason I was considering that way as I already have two square body K chassis'.

[68 TT]

Made some progress and got the frame cuts all welded up so it will be strong enough to move around and do the rest of the fabrication work to mount the body.

After all the fabrication work is done I will tear the whole frame down, finish weld all the modified areas from both sides and reinforce the whole thing so it is stronger than it ever was before.

I need to get it into my driveway where I can level the chassis out perfectly then I can mount the bed securely to the frame where it needs to go and fabricate the cab mount brackets to match the new cab location.

First pic is 67 body on an unmodified square body K10 frame and the second is with it on the modified & shortened wheel base version of the same frame.

The cab & bed need to come forward a little in the second pic and are just loosely set in place to get them out of the way.

[68 TT]

Originally Posted by Rob H.

Well that's alot of the reason I was considering that way as I already have two square body K chassis'.

The truck frames will work great but stay away from the Blazer as the frame is substantially different out back and would require a ridiculous amount of body lift to get the cab lined up with the bed. They would make a great rear mounted fuel tank donor though. That is about all I am going to get out of the one I have.

[propanemudtruck]

Nice work so far. I'm doing a similar project in the 4x4 section, with a short short wheelbase final product for an ultimate plow rig. It's the same as the K5 wheelbase but using a K10 frame to start with. In my build link you can see that I took the kickup right out of the frame to get away from modifying the body with notches or anything for body/frame clearance. With two truck frames I think this might make for a nice LWB or SWB truck, just cutting the kickup right out.

Good Luck!

[68 TT]

Originally Posted by propanemudtruck

Nice work so far. I'm doing a similar project in the 4x4 section, with a short short wheelbase final product for an ultimate plow rig. It's the same as the K5 wheelbase but using a K10 frame to start with. In my build link you can see that I took the kickup right out of the frame to get away from modifying the body with notches or anything for body/frame clearance. With two truck frames I think this might make for a nice LWB or SWB truck, just cutting the kickup right out.

Good Luck!

I originally was going to make a K5 wheel base ultra short bed truck using the 84 K5 Blazer chassis but decided I wanted the truck to be more useful around the house so I went with the K10 chassis instead.

I don't care for the look of a long bed C10 but as a 4x4 it doesn't look too bad so I may just leave it as a long bed now instead of doing the extra work to make it a short bed. I did leave enough straight area of frame under the bed to be able to cut out the extra 12" to make it a short bed if I change my mind in the future.

I will take a look at your build and see what you have come up with.

[68 TT]

Made a little progress. Just too darn hot to do much.

Got the steering column hooked up so it was steerable then got it out of the back yard and into the driveway.

Got it leveled out and cut the bed shims to get the intermediate rear rail to clear the back of the wheel arch in the frame then drilled the new bed mount holes & bolted the bed in place.

Fought with the cab for a while trying to get it squared up but it kept pivoting around. Got it close enough I could measure for the cab mount brackets.

Cut out most of the 1/4" steel plate pieces to build the new cab mount brackets and drilled all the flange pieces for the mount bolt holes.

Once I find the body mount bushings I am going to use I can bolt them to the cab and get the cab mounts tacked together and in place so I can drill the frame for the mount bolts.

After the cab is locked down I can work on fabricating the core support mount brackets that will be welded to the front spring hangers and secure the front clip.

The next step will be getting the drivetrain installed and make this pig run & drive again. I'm considering dropping the engine from my Malibu into this thing to get it running sooner and putting the EFI motor into the Malibu instead of the truck.

[68 TT]

Went to the wrecking yard to get a filler neck from a K5 to use with the Blazer tank & fuel door assembly I took off my donor K5 and came home with a nice seat from a 1990 regular cab new body style truck.

The seat in my 67 is a wasted rusty POS so this is a welcome addition.

Fits like a glove with a couple inches of clearance at the sides to clear the arm rests and the mount brackets fit the 67 cab floor like they were meant to be there. All it needs is a little reinforcement plate on the back side of the floor to reinforce the mounting bolt areas as they are not where the stock seats bolted up.

I did get the filler neck too after killing a few dozen wasps mid extraction process.

[68 TT]

After I picked up the "new" seat for the 67 I decided to be brave and remove the carpet to see how bad the rust really was. Up until now I had left it in place not wanting to know. Ignorant bliss.

I knew the tunnel had shifter holes cut in it and there were spots on the driver side where I could see daylight but just didn't want to deal with it.

Turns out it isn't as bad as I thought. Definitely needs the driver side front section of the floor pan replaced and the kick up area on the passenger side is thin but not rusted all the way through yet but needs replaced too.

The passenger side rocker and inner rocker are rusted through and the driver side rocker has been crushed so it probably needs both too. A little cancer at the floor to rocker transition area so the outer edges need replaced.

Saw that the bottom of all four outer cab braces need replaced on the support structure while I was under there fitting the cab to the K10 chassis so those all need replaced too.

The area under the seats is in great shape as is most of the passenger foot well area.

I am going to keep my eye out for a better cab at the wrecking yard but I can make what I have serviceable with pieces from the K5 floor pan to keep me from falling through the floor while getting this thing on the road and working all the bugs out of it.

When it comes time for body work and paint I hope to have found a good cab to work on by then and can have it ready to bolt onto the frame before I take the truck off the road to limit down time.

I found what was left of the build sheet behind the back seat and another partial document under the seat that said a dealers name in Seattle and the Fremont build plant on it. I will see if I can get a decent pic of it tomorrow. It is stuck under the seat springs and I would destroy it trying to get it out.

[Captainfab]

Looks good

I've used a square body frame under a '62 C10.....they don't work so good for a 2wd swap IMO. I've always said that they are more suited as a 4wd frame swap. I like your idea of stretching the frame under the cab.

[68 TT]

Originally Posted by Captainfab

Looks good

I've used a square body frame under a '62 C10.....they don't work so good for a 2wd swap IMO. I've always said that they are more suited as a 4wd frame swap. I like your idea of stretching the frame under the cab.

Thanks. Stretching the frame under the cab made a huge difference in the way the body can sit on the frame and will make it look more like a stock 4x4 which is what I was after. I really didn't want another lifted truck with huge tires on it. 31-32" tires with a 3" body lift just doesn't look right to me so it would have to have bigger tires on it to look right.

It is coming along but I have a bunch of work to do still. I am hoping to have it moving under its own power again in a couple weeks.

The engine, trans & transfer case are ready to go. I just need to finish the cab mounts and get the thing bolted back together before they go in.

I am working on a deal to get a better cab right now so hopefully I can make the deal happen. The current cab needs a bunch of work that I would like to avoid if possible. The possible new cab is a factory A/C cab too so that would be a nice thing to have.

[madmopar]

SUBSCRIBED!

I love what you did. I recently picked up a 70 LWB "the possum" project truck that is already on a mid 70's chassis. The PO didn't "stretch the frame" like you did so it sits quite a bit higher. I really like the stance of yours better though. You're making me want to tear it all off and do it this way...

I've got a lot of work to get mine even to the point you're at though.



Here's my parts donor truck:



Its a 75 cab on a 70's? blazer frame. I'm gonna use thoe motor, tranny, transfer case, lockout hubs, and possibly the blazer tank.

Sorry for pirating your thread. Just wanted you to know I was working on a similar project, but going about it a different way.

Check out my build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=415134

[68 TT]

Originally Posted by madmopar

SUBSCRIBED!

I love what you did. I recently picked up a 70 LWB "the possum" project truck that is already on a mid 70's chassis. The PO didn't "stretch the frame" like you did so it sits quite a bit higher. I really like the stance of yours better though. You're making me want to tear it all off and do it this way...

I've got a lot of work to get mine even to the point you're at though.



Here's my parts donor truck:



Its a 75 cab on a 70's? blazer frame. I'm gonna use thoe motor, tranny, transfer case, lockout hubs, and possibly the blazer tank.

Sorry for pirating your thread. Just wanted you to know I was working on a similar project, but going about it a different way.

Check out my build thread: http://67-72chevytrucks.com/vboard/s...d.php?t=415134

Looks like a good start on your project having the spare truck to use for parts & drivetrain. Good luck with it.

I would really want to stretch & alter the wheel base of the frame if I were you after seeing how high these conversions have to sit off the frame to make the cab & bed line up. It doesn't look like the PO of yours altered the wheel base to match the older body style. While fixing this you might as well stretch the frame while you are at it. It won't take much more time to do.

I hope to make some progress on my project tomorrow while my wife is at work and the girls are at the grandparents.

[68 TT]

Finally got a chance to work on the 67 again.

Got all the cab mount brackets cut out, fit to the frame and got the cab located properly & bolted down.

Got the small brake pedal from the 67 replaced with a disc brake pedal, fit the pedal assembly with a dual function brake switch for the PCM & TCC, and modified a square body brake booster to fit the stock 67 pedal bracket & firewall. Two mount holes were in the right spot, just needed to drill two more holes to match the 67 pedal bracket. Now that it is in place I can mark it up and trim off the excess material to make it look right.

I still need to put the newer master cylinder & prop valve on but that won't take long. Once that is done I can drop the drive train into this thing.