Halfbreed - GMC Z71 + IH Extd Cab

[nuke1]

Now that is looking amazing, as for the runaway, i could not control my laughter when I saw that, too funny, but not funny. I really like the way you are goin about building this. one question, thou. Do you plan on shortening the bed or lengthening the frame if need be, just wondering, I do not think that I saw that here, but I could be wrong.

[sparkydog]

Originally Posted by nuke1

Do you plan on shortening the bed or lengthening the frame if need be, just wondering, I do not think that I saw that here, but I could be wrong.

Yes I have the 8ft bed. I will need to shorten it to approx 6.5ft.

[NONHOG]

Just reading this time instead of skimming through the pics.
Today I find out your not a youngster that I assumed you were. Heck your an old fart like me.
Aleve and margarita's, I can relate.
Love the build, keep up the great work.

[ERASER5]

I am in awe.

[Stitch]

x2

[sparkydog]

Aw shucks guys, thanks for the compliments and encouragement. I have learned that it really doesn't take much talent to rip stuff up - just balls and a sawzall. The talent comes in putting it back together!

Here I am now with more sheet metal gone than I ever expected. All for perfectly good reasons, however the project is still not quite to the turning point of CONstruction. When I get to the point that I am tack welding on a routine basis I will feel more like I deserve your compliments!

[sparkydog]

Originally Posted by NONHOG

Aleve and margarita's, I can relate.
Love the build, keep up the great work.

Yeah one of the motivators for me to try this project was I'm starting to get bad enough arthritis that I know I've only got a few more years left before I won't be able to do stuff like this. Waaaaaaah..

OK back to work.

[sparkydog]

Originally Posted by 67ChevyRedneck

Very cool!

Some friendly advice? In case you weren't planning on doing this, I'd set the cab in place (out of the way) and fully mount the bed the way you want it (wheel well centered, bed height, etc...). That way, you don't accidentally mount the cab "too low" and have to raise the bed floor, that is, if you didn't want to do that. Just offering up an idea. It's looking great

Yesterday I made all the necessary measurements and then jumped on the computer and sketched this up. There are three different types of cross rib under the bed of the IH. Each has a different height. I did the layout as if I was notching the two taller ribs down to the height of the shortest one @ 1.25". Also allowed for a .25 rubber spacer between the bed and the top of the frame rail.

When I do all this stack-up, it says that "on paper" the lip of the bed would end up .6" lower than the corner of the rocker panel (not the bottom of the flange lip which I don't consider the visual bottom of the cab). What that means in English is if I want to be "perfect" I should drop the IH cab body .6" (call it .75") around the GMC floorpan.

Now dropping the body is extra work compared with just laying the remnants of the IH floor onto the GM floor in a simple lap joint. Not too much extra but extra none the less. The other choice is to just spacer the IH bed .6" higher over the frame and call it good.

Hmmm, decisions, decisions. If it had been a bigger difference, like 1 or 2 inches then I would do it for sure because I want a low ride stance and will plan to use an aftermarket lowering kit. But .6" is right at the ragged edge of being worth it.

[383Ram]

Neat project. I am digging this. I read this thread yesterday and was impressed.

As far as the floor deal goes, i dont think the on paper .6" difference is worth it to channel the floor into the cab. I would rather space the bed up to where it need to be and get the stance with the suspension. I dont know what exactly the floor looks like between the two vehicles, but would it be a little better to put the Chevy floor on top of the remnents of the IH floor instead of the IH floor on top of the chevy? That will help a tiny little bit.

[FRENCHBLUE72]

Really diggin this project....

[sparkydog]

On Sunday I finally took the GMC headlights off just for something to do. I figured somebody was eventually going to ask me why I was trying to use them on the IH grill.

Then on to some real work which was to add a temp brace to the front of the cab and then cut out the IH floorpan.

And I even managed NOT to cut through the GMC floor - which has been known to happen with me!!!

[sparkydog]

I also did some minor trimming along the corners of the GMC firewall and this allowed me to position the cab farther forward and closer to final ride height. I still can't drop the cab down to the proper level until I do a little more trimming on some cowl interference. But now I can begin to make my final decision on the fore/aft placement of the cab relative to the front wheels. In these next pictures I have it as far forward as I might want to put it - this would be where I would have to section the nose of the truck or else it would look like a dork truck.

[sparkydog]

After doing all this and getting the cab lower and being able to slide it fore/aft, I was able to actually "see" the real truck that was in my head and on those crude photo sketches. It was an important motivational milestone. Felt great!

Boy am I getting tired of cutting..

[BlueJeep]

Originally Posted by sparkydog

Now dropping the body is extra work compared with just laying the remnants of the IH floor onto the GM floor in a simple lap joint. Not too much extra but extra none the less. The other choice is to just spacer the IH bed .6" higher over the frame and call it good.

Hmmm, decisions, decisions. If it had been a bigger difference, like 1 or 2 inches then I would do it for sure because I want a low ride stance and will plan to use an aftermarket lowering kit. But .6" is right at the ragged edge of being worth it.

If you weren't already splicing the floor from the GMC I might say space the bed up...but since you're this far...drop the cab down to where you want it. It might even be easier to work with, depending on how it lays out.

Also, after seeing your last photos, I vote for slide the cab back and center the front wheels. I think the work of sectioning the front clip wouldn't be worth the reward. Plus, looks like your steering column/wheel are already back too far into the passenger compartment in your "forward" position.

Love the project, I'm a secret IH fan as well!

[sparkydog]

Yeah the basic tradeoff is:

Cab forward means I HAVE to section the hood and fenders and find a shorter steering column and change the brake pedal distance. The benefit is I get a longer bed, the "cooler" look that I want and less work to the back of the cab bottom (where it will hit if I slide the cab back).

Cab back means it looks OK with the stock IH fenders and hood. Don't have to mess with the steering column or brake pedal. DO have to mess with the bottom rear of the IH cab because it will hit the frame/fuel tank. Also means the bed will end up at 6.5 ft or so.

And on the sectioning of the nose - I know what and how I would do the hood but the more I look at the fenders and their funny little IH swoop thingy, the more I don't know a clean way to shorten it up without rebuilding the whole side.

[BlueJeep]

Originally Posted by sparkydog

Yeah the basic tradeoff is:

Cab forward means I HAVE to section the hood and fenders and find a shorter steering column and change the brake pedal distance. The benefit is I get a longer bed, the "cooler" look that I want and less work to the back of the cab bottom (where it will hit if I slide the cab back).

Cab back means it looks OK with the stock IH fenders and hood. Don't have to mess with the steering column or brake pedal. DO have to mess with the bottom rear of the IH cab because it will hit the frame/fuel tank. Also means the bed will end up at 6.5 ft or so.

And on the sectioning of the nose - I know what and how I would do the hood but the more I look at the fenders and their funny little IH swoop thingy, the more I don't know a clean way to shorten it up without rebuilding the whole side.

I was looking at the fenders too wondering how you figured on doing that.

I'd also add to your list of having to change in the forward position: seat mounts for the front seats and I'm also wondering how you'd fit heat/AC under a dash if it's that far forward...

I wonder if another way to achieve the look you're after with the front would be to kinda do the opposite of what chopped top guys do with the windshield. Instead of laying the top back, what if you would lay the bottom forward, and shorten the hood as you've planned. That way your fenders could stay stock, your hood could be shortened, and the nose would look "stubbier"... Maybe you could take the "kick" out of the front of the door that way, and have the leading edge of the door be straight. Think 61-63 Chevy truck vs 64-66 Chevy truck. Hope I'm conveying what I'm thinking.

[67ChevyRedneck]

I think the 6.5' bed would look great

[67_C-30]

Originally Posted by sparkydog

Yeah the basic tradeoff is:

Cab forward means I HAVE to section the hood and fenders and find a shorter steering column and change the brake pedal distance. The benefit is I get a longer bed, the "cooler" look that I want and less work to the back of the cab bottom (where it will hit if I slide the cab back).

Cab back means it looks OK with the stock IH fenders and hood. Don't have to mess with the steering column or brake pedal. DO have to mess with the bottom rear of the IH cab because it will hit the frame/fuel tank. Also means the bed will end up at 6.5 ft or so.

And on the sectioning of the nose - I know what and how I would do the hood but the more I look at the fenders and their funny little IH swoop thingy, the more I don't know a clean way to shorten it up without rebuilding the whole side.

In my personal opinion, I think the shorter 6.5' bed would would look better, especially with the crewcab. But its your truck and you have to do it like you like it. Either way, I'm a big fan of your truck!

[sparkydog]

I have a little diversion tonight. A guy from the IH forum where I am also posting this build wants the remnant of the 67 pickup cab that is left over from the mayhem. So I got to use my bed dolly a little and wheeled things out of the way and brought the cab down from it's loft. Now we can all see the junk in my trunk.

[sparkydog]

This sketch/photoshop is sort of my rendering for my project. In this photo I got the shorter nose and the longer bed look that I liked. In order to pull these proportions off on the real truck I will have to position the cab about where it is in post #62 and shorten the nose about 3-4". When I did the crude chops on the photos I sort of screwed with the swoosh thingy on the fender.

It's really going to come down to how aggressive I want to go after my dream and what am I willing to compromise on to manage risk and keep the build moving along.

If I leave the cab in this location - let's call it the most extreme forward I would want to go, then the bed only need about 6-8" taken out of it in front of the fender wells. For every inch I slide the cab back in order to make things easier, another inch comes off the bed length. To get the cab far enough back so that the wheels are in the center of the stock fender, that's about 6" back so that means 12-14" comes out of the bed.

[sparkydog]

I guess this is about as close to a rendering of a stock fender length. Even in this one I have the front wheels 1-3" back from centerline of the fender well. And to me, at least in the photo's perspective (which isn't the same as 3D real world) the truck just starts having the "peculiar" IH look that... well it doesn't do it for me.

[383Ram]

I am intrigued by pulling the cab foward and shortening the nose. I think your on to something there, but obviously you have already seen some of the issues your going to have to deal with. I like the cab foward modern approach. I say do what ever you have to do to keep the cab foward and worry about the rest later (although i know you need to keep the whole project in mind to do this.) The sorter bed does,t really matter to me, but it almsot souns as if you want the long bed so you can haul stuff---unless i missed something along the way. Looks good though.

[ERASER5]

2 questions.

1. Is the rubber chicken Bonney's cousin?

2. How do you lift and move stuff like that cab? I have not seen a hoist in pictures.

[sparkydog]

Originally Posted by ERASER5

2 questions.

1. Is the rubber chicken Bonney's cousin?

2. How do you lift and move stuff like that cab? I have not seen a hoist in pictures.

A1: The chicken is my project mascot. He supervised my jetboat restoration a few years ago.

A2: I'm using 2 floor jacks, 4 jack stands, 2 home-made dollies, 4 jack stand extenders (modified wheels) and A LOT of wood blocks and beams.

Now that the stock IH firewall and floorpan are gone and replaced with the GMC stuff I can lift one side of the cab myself when I need to. I've been getting a workout but so far haven't blown out my lower back.

[sparkydog]

Originally Posted by 383Ram

I am intrigued by pulling the cab foward and shortening the nose. I think your on to something there, but obviously you have already seen some of the issues your going to have to deal with. I like the cab foward modern approach. I say do what ever you have to do to keep the cab foward and worry about the rest later (although i know you need to keep the whole project in mind to do this.) The sorter bed does,t really matter to me, but it almsot souns as if you want the long bed so you can haul stuff---unless i missed something along the way. Looks good though.

Here's the tradeoff in a nutshell: