Hmmm, I used the Rock Lizzard recipe, used two leafs per side, got 2" in the back. The front was good for an inch, The stock isolators seem to just bulge out. I'm considering an aftermarket isolator.
The ride is greatly improved since the tired stock springs have been bolstered with newer leafs. I may have spent around $100. I'll see about getting pics if you want.
Edit: I put '99 leafs on an '87 spring pack. All the leafs appear to be the same thickness, I can verify this if you like.