Trying to switch out my 4.2 258 in my 89' YJ for a 4.0 Liter. Ive got the engine but still need the transmission (AX15) and transfer case. Also, the items listed below. I think thats all I need to do the swap, but any advice or input is very much appreciated. Thanks guys! (and gals)

91-95 4.0 Man ECU
91-95 6cyl Engine Harness
91 4.0 Dash Harness