Ok, Yes I can go buy a 4X4 but I dont want to!! I have a 2000 Silverado LS with a 4.8L, Auto trans, extended cab 4X2. I am picking up a 2001 Silverado LT with a 5.3L, auto, extended cab, 4x4. The 4x4 body and interior is trash, but the driveline is great. For around 2k and some labor I want to swap the body. ( Cab, front clip, bed ) Everything is straight forward to me, but the 4x4 system. The only thing I am keeping from the 4x4 cab is the computer and whatever 4x4 switches/ wires I need. Here is where I need the help. I think. How is the 4x4 wired through the truck? I think the 4x4 push button switch is wired from the switch to the computer. I dont know where the TCase wires go to. I think they go to the fuse box under the hood. I assume the wire harness on my 4x2 is the same as the 4x4 just some wires aren't fused or connected. Any help on where to begin or how to do this would be great. Thanks.