At 4" youre most likely going to need AT VERY MINIMUM LCA's... but really SHOULD have new UCA's...
Brake lines...
You can tcase drop, or sye.. possible to be fine with a 1" drop.. mine always were around that height...
Rear shaft... SYE means SLIP YOKE ELIMINATOR... a SLIP YOKE means the YOKE slips in and out.. notice the front shaft is bolted to the yoke, solid, and the rear slips in and out?
Track bar.
Make sure you have a fresh steering stabilizer.
Bump stops.
Dont get over a 1" shackle.
And that AAL is going to ride like ass.
Now those were the facts.
Now for my opinion.
If youre going to do it, get some f150 or the like coils, and search "bastard pack" for the rear, get 3-3.5" inches, then just extend brake lines, and you can not worry about control arms for now.
Seems like youre trying to go the cheap route, as my current xj is.
Good luck, and Good jeepin!