The transmission lengths will be the same, so you'll be able to use your rear driveshaft. I don't know about front as i converted to a manual xfer case at the same time. You'll need to use the old computer as well as shorting a few wires on the old harness. here is an old thread that helped me with the wiring (second page)
http://www.therangerstation.com/forums/showthread.php?t=77525&page=2
edit: also good luck with the clutch master rod out of the donor without breaking it. be prepared to buy a new one if you don't have the right tools.
When you say old computer do you mean from my truck or the donor? Also what or why do I need to short wires in my harness...since I have the complete donor shouldn't I have everything to plug in like factory? I am going to pull the engine and trans from the donor truck and my truck, swap everything over (pedals, ,brackets, etc) then put the donor engine and trans in my truck. Hopefully everything will be plug and play? Im not sure if i can use my original computer or the one from the donor. I don't know a bunch about the computer part of things or if they are VIN specific. I was planning on using the donor engine harness, trans harness, etc. P.S. While the donor engine and trans is out I will put a new clutch etc. in before I install it in the truck. Anyone pulled the engine and trans together on one of these? Better yet anyone stab in a complete engine and trans in one of these? If so does the front clip need to come off or can you jockey it in without?
This truck was my son's xmas present from my dad. He gets his license in about 9 months so I got time! I was originally planning on a rebuilt trans until I found out how pricey they are for these things...then I stumbled into this donor. I figure it would be a good experience for my son to learn to drive a manual trans and clutches are cheaper than a rebuilt 4r44e.