85 body on 74 frame

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Mitchell95

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well my 74 front clip is rusted and the cab is pretty bad too but I have an 85 k10 parts truck with a good cab minus rust in floor pan and the front clip has no rust at all, I know for the swap I’d use body mounts for the year of frame but my question is what would be involved to make the 85 clip work on the 74 frame?
 

Rusty Nail

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Next to nothin? The core support is the main difference I believe everything bolts together. Since you have th he '85 support I think it is a straightforward swap.
Too bad about them roundeyes though... :(
 

Mitchell95

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I like the look of the 85 more but yeah I would honestly have rather kept the 74 as the round eye was falling on me but I might just use the 85 cab and buy a 74 front end to use I haven’t decided but I know the 74 cab is bad I got after it with a brush wheel and it’s got bondo in all the rust spots and has rust all through the pillars I found
 

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The different core support may require the other fenders but I won't say for sure..good luck with your project!
 

bucket

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The core support mounts on the frame will not quite be in the right place. The amount of work needed to overcome that minor issue can vary from truck to truck. It likely can be overcome with just a little bit of hole slotting in the core support.
 

Mitchell95

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So basically the 85 front clip won’t exactly bolt on cause the frame core support mounts I’ve seen on some frames they had to move the mounts back and re weld them if that much is involved I’ll just find find new finders and a core support and keep the round eye front end
 

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While you're shoppin, I am about halfway in the market for a roundeye clip myself.
That '88 better watch it's ass! That may be all it ends up with lolol.
I think the only thing that saves it is the fact it only has one headlight. I can't get down with the stacked look at all.
Don't get me wrong..there are some super cool 85s runnin around but I prefer the roundeyes.

And the grille man...the old school grille is da bomb diggity!
 
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bucket

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So basically the 85 front clip won’t exactly bolt on cause the frame core support mounts I’ve seen on some frames they had to move the mounts back and re weld them if that much is involved I’ll just find find new finders and a core support and keep the round eye front end

Like I said, it varies from truck to truck. Some folks say they have to move the mounts or replace them. Some folks say it fits together ok. I did the swap on my truck (just the opposite way) and only had to fiddle with the mounting hardware and the adjustments.

But I vote to keep the round-eye front end! I like the older front sheetmetal on older trucks... It just belongs, lol.
 

Mitchell95

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I’ll just set the 85 front clip on my 74 frame tomorrow as the 74 cab is still bolted to the frame and if the core support doesn’t line up I’ll just use the 85 cab and put the round eye clip back on it, plus I have a 74 core support coming in the mail next week anyways.
 

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Welcome to GMSB from Virginia please keep the pictures coming too:boti:
 

Mitchell95

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So if I use the 85 cab and use my 74 wire harness and wind shield wipers in the 85 cab my 74 clip will still line up correct? Well I dropped the 85 clip on today and lined up so far with the 74 cab on it so for now I’m sending my 85 cab to body shop and dropping my 74 cab on the 85 frame (the 85 frame is bent on the back) really just gonna use my 85 frame as a farm truck basically with the 74 cab.
 
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bucket

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So if I use the 85 cab and use my 74 wire harness and wind shield wipers in the 85 cab my 74 clip will still line up correct?

The clip will fit fine, yes. You will need to drill a couple new holes to get the '74 wiper posts bolted in, and also elongate the top mounting holes in the fenders because the bolt holes are in a slightly different place on the cab. That's no big deal at all. But using your '74 harness and switches inside the cab means you will need to get the headlight and wiper switches mounted in the dash that only had a headlight switch originally. There's actually quite a few differences between the cabs, but it's all minor stuff that is easily dealt with.
 

bucket

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Or you can just use the '85 cab with it's stock harness, switches, steering column, wiper motor, etc. The '74 front lighting harness will plug right in. Or, it should. I know that the later 70's pinout the same as the 80's. Going that route, you will still need to use the '74 wiper posts.
 

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