ls 4x4 swap questions

[marc55]

I have tried to find some info about transmissions and transfer cases options on an Ls swap and have not found what I am looking for. My project is a 55 Chevy body on a 78 4x4 frame. I want to install a 5.3 engine and am wondering about controlling the transmission and transfer case. Can the engine harness be easily modified to control a 4l60e and a push button transfer case? Or am I looking at buying an expensive controller? I would like to buy a complete drive train out of something like a Tahoe but I don’t know how complicated it is to work with the vss system and I don't want to buy stuff I ca not use. My other option which I am leaning towards now is to adapt a 7004r to a manual np241. Also on the 78 frame are there any issues with the oil pan clearance?