engine upgrade

I have an 89 XJ Larado 4x4 auto. I have also an complete (engine,tranny,t-case) out of an 98-99 XJ. I am in the middle of the exhaust manifold repair and was contemplating swapping the drive trains. I realize that all the electronics(engine manag.) would need changed, a 98-99 harness. My question, is how would this affect all the other electrical items on teh interior? Radio, steering column, ignition, etc.. Or would this get into removing all interior and upgrading everything for sake of the harness to run the engine. They are both 4.0's.

With going from a renix engine to a HO engine you would have to swap the entire harness from under the hood and inside since the 10 yr difference included other electronics that probably wouldn't be in your old style.

Thats what I figured, a lot of work. My wife has an 95 wrangler w 2.5, I might hold onto the engine and stuff to one day transplant into hers. I have already swapped the t-bodies, with a noticable change in low end torque.