A body lift will do nothing to help with the clearance of your sump. A 2" suspension lift also won't help enough. I don't know how bad clearances are on leafies, but with a 2" suspension lift in my coily, I had about 2" suspension travel. Change the sump and modify the the pick up.
G16 sump. Keep in mind this has a 2" lift. You can see that the axle tube will strike the lower portion of the sump at the front, just forward of the plug:
G13 sump. Conforms to the axle much better:
As requested, here are some photos of the two pick ups and their sumps (G16 LHS G13 RHS):
The G13 sump is deeper (presumably to allow for the smaller size of the well).
I removed the windage tray (I think that's what it's called) to allow clearance of the top half of the G16 pick up:
Cut and grafted G16/G13 pick up:
Two halves glued together:
Hybrid pick up installed for test fitting of sump:
