Aligning body panels...

[GMC Guy]

does anyone have any little tips and tricks when it comes to aligning the doors and fenders? i'm tired of fighting with getting the doors lined up.... just trying to finish up the cab swap from a 79 to a 74 cab. and getting the doors mounted is holding back the process. any advice or little secrets would be much appreciated

[texasfunk]

always start from the back, you can't adjust the cab, so that small corner is your starting point, get the door on, and the back aligned with the cab, then do the fender, and remember, always start by the marks the orignal hinges/bolts line up, if its all OEM parts, 90% of the time it will be on the money!

[Rpratt]

It sucks. If you hang the fenders first, you can't get to the hinge bolts for the doors, if you hang the doors first you might have a hard time adjusting the fenders to match.

I have always had a better time hanging the doors first and then the fenders, obviously there are multiple ways to do this....... and they are all do-undo...do-undo...do-undo....

[Keith Seymore]

Originally Posted by Rpratt

It sucks. If you hang the fenders first, you can't get to the hinge bolts for the doors, if you hang the doors first you might have a hard time adjusting the fenders to match.

I have always had a better time hanging the doors first and then the fenders, obviously there are multiple ways to do this....... and they are all do-undo...do-undo...do-undo....

Yep - shim like crazy!

Get the doors to match the cab back first; then set the fenders, hanging them by the top vertical bolt (underhood). Get the feature line to match the door by shimming there.

Next, adjust the in/out by shimming the top most horizontal bolt. You can access that bolt by opening the door.

Lastly, shim the bottom rear anchor bolt to match the curvature of the door.

In the factory, we used a little magnet with a 1/4" tongue on it, inserted between the door and fender to set the gap. If you could make one of those (or have a friend hold a 1/4" piece of wood in the gap) while you adjust it would take some of the guesswork out of it.

If all of the above fails, you can always use "the big hammer" and "the big stick"....

[GMC Guy]

thanks guys, i think i'll start by getting some new striker bolts, and hinge pins (just to make it that much easier)
but where i've been running into trouble is where the door meets the cab on the handle side. it's weird, the middle of the door lines up fine with the body lin of the cab. but the door still needs to be "sucked" into the cab at the top edge (below drip rail) and at the bottom corner nearest the bed... maybe adjusting the striker bolt will help? i'm not looking for perfect alignment, i'll worry about that more when it gets painted someday. i just want it water tight lol and no whistling going down the highway

[54Caddy]

what you got a cab dang lucky guy ahahha im looking for one now too tired of this 2barrel carb, there like 400 for a new one and they told me still there not any good, so im looking for a cab then a plan and simple edelbrock intake and a 500 cfm carb will come ahahah

[GMC Guy]

Originally Posted by 54Caddy

what you got a cab dang lucky guy ahahha im looking for one now too tired of this 2barrel carb, there like 400 for a new one and they told me still there not any good, so im looking for a cab then a plan and simple edelbrock intake and a 500 cfm carb will come ahahah

lol i think you misread
i swapped my whole cab with a cab off a 1974 gmc. no more rust, and no more smog :]

[54Caddy]

oh i know thats what you ment im dieing to get rid of my smog stuff damn. where is the vin plate on the older cabs, and how do you go about registering it and canceling your old cab??

[GMC Guy]

well i bought a 74 parts truck for $200, and pulled the cab off. recycled everything that wasn't re-usable. the key is to register the smog exempt cab in your name. the vin is located in the driver side door jam. i non-opted my 79 during the whole swap. now all i gotta do is get the truck back on the road and get the registration re-newed. the dmv will never know the difference :]

[Davidmichael]

If you can, drill small pilot holes before you pull a part off, then you can just toss the piece back on and use a drill bit to line everything up.

[bigblock73]

Originally Posted by Davidmichael

If you can, drill small pilot holes before you pull a part off, then you can just toss the piece back on and use a drill bit to line everything up.

In this case, that won't work...he is doing a cab swap.

But your method does work, most of the time.

[gchemist]

Start at the doors and work forward. It's not easy.

[STOCKISH]

Lots of patience man, lts of patience. It is soooo worth it when youre finished and the doors shut just as easy as a new truck!

[spudz]

also make sure your hinges are tight or you will never get anything right.

[1LowToy]

Make sure the truck is on the ground. There is a whole lot of frame flex. If your trying to do this on jack stands everything will be wack. Actually you should have switched everything over to the '74. The truth is California identity is the frame for being whatever year it its.

[GMC Guy]

there's no way in hell that the old lady in the dress is gonna crawl under the truck and look for the vin on the frame. they'll never be able to tell the difference. all they look at is the VIN on the cab itself, just like any other car or truck