I recently built a winch bumper and with the stock springs the front end of my 96 XJ 4L was sagging. I picked up a used set of front springs from an ZJ that had a V8. Installed them and almost got 2.5" of lift. Wow! The job was reasonably easy to do, used lots of penetrating oil and I saved a ton of money buying used. Went for a road test and the front end no longer feels mushy it's awesome.
I priced new springs 160.00 $
Used " 30.00 $
All the best
Gman