Okay, here's what I've decided to do and why...
I'm using CJ rear shackle hangers front and rear with the rivet-removed/one hole forward mod. on the front. I'm using YJ rear springs in the rear and YJ front springs in the front. I'm cutting the eyes off the main leaf in the CJ rear packs and adding those just under the main leaf in the YJ front packs. I'm doing this for three reasons.
#1. to fight spring-wrap on the front springs. I don't anticipate this being a big issue and I figure that the extra leaf will largely take care of it.
#2. I'm swapping in a V-8 and I'm planning on using a heavy winch (nothing beats an 8274!). Even though my 5.3L is actually lighter than a 258 or 304, it's heavier than the 2.5L that was in the YJ that the springs came from. The 8274 is just a beast.
#3. I'm anticipating some settling and sagging and I'm trying to get as much service as I can from the springs before I have to replace them.
I'm also planning on running a hard top some of the time and a full-sized spare all of the time so I may take the 2nd rear CJ leaves and incorporate them into my rear YJ packs.
To make it all work, I bought a set of Currie greasable shackles for the front and rear. Anyone who has used CJ shackle hangers and YJ springs will tell you that the bushings are different sizes. I bought CJ rear shackles and the hanger bushings are the right size but the spring bushings are too small. I bought YJ front shackles and the hanger bushings are too big but the spring bushings are correct.
Lucky for me, it doesn't take a rocket scientist to figure out that I can just swap the hanger bushings on the front for the spring bushings on the rear and everything will be the right size.
The question now is this: Have I just negated any flex or ride advantage of the YJ springs by adding leaves to the packs?