[Prerunner1982]

Now that I think about it a bit more, my math isnt all right. The shackle part only changes 1 end of the suspension, the front remains unchanges (Except for the 4" lift leaf springs). With the axle mounted in the middle of the leaf the total lift at the shackle end should be reduced as the "lift" is only at one end and not right in the middle.

I still think you should try it with stock height leaf springs and see where that gets you.