2wd 6.5 2500 to 4wd (Help?)

So a friend of mine has a 96 C2500 with a 6.5 TD in it. He uses it to haul cars around for my other friends and I pretty regularly. One problem he's always had was getting the thing stuck in mud with a trailer behind it. I'd then have to pull him out with my blazer (which didn't even struggle to get him out.) It seems like he gets stuck in the littlest bit of mud. So when I found a 96 2500 4x4 without an engine or trans for $400 I jumped on it. Thought I'd help my buddy out. Just picked it up yesterday. We plan on pulling the 6.5 out along with his freshly rebuilt 4l80e and putting it on the 4x4 frame. Then doing a cab swap (the donor doesn't have a title and the cab is pretty beat up.) Before any of this can happen we have to shorten the frame because the donor is an extended cab and the 6.5 is a single cab. That's not a big deal, my uncle has shortened many frames and agreed to help me. Here's where the questions start. The donor came with the t-case (EDIT: a quick search points to it being a NP243C.) It's the push button one. So the first question is, what needs to be done to get the push button wiring to work in a 2wd cab? (I know floor shift is better but we're rednecks on a budget here.) The second question is, to get the 2wd 4l80e to mount up to the t-case I was told all it takes is an adapter and a cut off wheel to shorten the output shaft. If this is true, what would be the proper shaft length? I'm sure I'll be able to measure the input of the t-case and find out, but it'd be nice to compare my measurements to someone else's. Also, the oil plug for the 2wd tail housing will need to be replaced with the 4wd plug. If anyone knows the part number for this I'd appreciate it. I'll try to get pictures and post them up for people to follow along.

Well, I dug into the parts truck this weekend and wasn't happy with what I found. The guy said it had the transfer case in it still, it doesn't.. somebody had cut the torsion bars in half the interior parts that I was planning on using we're not there.. but I'm still wanting to do this. New plan is to go hunt for some torsion bars and a 3500 transfer case because he wants a floor shifter instead of push button. It'll also be easier to install.

Why use a cut off wheel you can mix and match parts to make a 2wd 80E a 4wd. Pull the output shaft from 1 to the other. You may have to break the transmission down some but with what your attempting to do you should like you know enough to accomplish the task. All diesels will have the beefiest parts offered . Gearing is pretty much what changes n the 1/2 3/4 1 ton vehicles. My 1500 6.5 burban has the 9.5 8 lug front and 8 lug 14ff rear and its a half ton.
Pulling torsion bars out on these old trucks are near impossible thats why they cut them. I had to take mine out not to long ago . I had to cut the support bracket for my torsion bars on my turbocharged 383 Yukon frame and tig weld it back together.
Your going to have to swap everything over from the six five its all different everything if the donor isnt a diesel then there where year changes also for emissions regulated stuff. Different ecm injection pumps ect.. If you need help I have a 96 burban 6.5TD 4x4 vin code f.
Sounds like adding a 4x4 to you buddys truck may be easier imo.

Mrich0908 said:

Why use a cut off wheel you can mix and match parts to make a 2wd 80E a 4wd. Pull the output shaft from 1 to the other. You may have to break the transmission down some but with what your attempting to do you should like you know enough to accomplish the task. All diesels will have the beefiest parts offered . Gearing is pretty much what changes n the 1/2 3/4 1 ton vehicles. My 1500 6.5 burban has the 9.5 8 lug front and 8 lug 14ff rear and its a half ton.
Pulling torsion bars out on these old trucks are near impossible thats why they cut them. I had to take mine out not to long ago . I had to cut the support bracket for my torsion bars on my turbocharged 383 Yukon frame and tig weld it back together.
Your going to have to swap everything over from the six five its all different everything if the donor isnt a diesel then there where year changes also for emissions regulated stuff. Different ecm injection pumps ect.. If you need help I have a 96 burban 6.5TD 4x4 vin code f.
Sounds like adding a 4x4 to you buddys truck may be easier imo.

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Adding 4x4 to his truck is technically what we're doing. We're going to be using literally everything off of his truck and just put it on the 4x4 frame. Right now I'm just trying to figure out the t-case issue. New torsion bars are ~$300 so that's not a big issue. The reason for wanting to cut the output shaft instead of tearing the tranny down is just that. It was rebuilt less than a month ago. I don't feel comfortable with tearing it down myself, and the trans shop is gonna want too much to do it. Plus if we screw up the output shaft we'll have to test down the tranny, so we might as well go the cheap route first lol. I've seen a few success stories so I'm confident.