4AC will NOT bolt in like a 4k/5k in a ke70. 4k/5k is a straight swap because everything is already there. If you want a 4AC you'll need:

AE71 pedal box
4a crossmember either AE86 or AE71
T50 G/box crossmember
T50 gearbox
4a engine mounts/t50 gearbox mount (rubber)
4a engine
T series front half tailshaft onto your rear half

That's off the top of my head. I know I have forgotten things, but did you even try a search on this? 30 seconds gone from my time and I found you this.