I don't believe the concept of that leverage on the TJ Unlimited is fully realized by most. The last one we set up coil overs on was dialed in to get the ride height exactly where we wanted it. The owner brought the spare over and we hung it on the swing out. The back went down about 3/8"ish, the front went up over an inch.
Sounds familiar. On my short TJ with it's heavy carrier, I consistently needed LJ rear coils to get the rear ride heights I was after. And the front would have a lighter coil than what others would typically use. I'm not familiar with the weight distribution on an LJ, but I can imagine that the teeter totter effect could be greater with the larger overhang.