If you change out the front suspension and c-notch the frame in the rear you can get really low without air bags. If you keep the twin I beams you are limited in how low you can get in the front.
jag xj notched into the frame a coupla inches or 2nd generation camaro sub will get it you as low as you should go without bagging. i notched the jag into my uni 2 7/8". i have now basiclly clamped a stick of 2"x2" 3/16wall inside the frame rail and notched to it. frame height there was 4 7/8" originally. i am also gonna stack another stick of 2x2 on top of the frame railand weld it all together. i finished welding the inner(lower) pieces in yesterday. i forgot to take measurements before hand of the front. BUT the rear i flipped an explorer disc 8.8 on top of the springs and pulled a leaf or two. the rear dropped about 8" and the front with the jag notched in to this level is an inch or so lower than the rear. so jag not notched and just a rear axle flip would probably net you 5-6" drop. not notching the jag in is way easier. esp since i did the experiment and ended up nothing mine 3 diferent times before i was happy. 1" notch not worth the trouble so i went 1 7/8". after going back and forth and trying to make myself say "close enough" on the ride height i wanted a week or so ago i finaly said NOPE and notched another inch. i am now finally happy after months of playing with it. mine should be welded in a rolled out for pics before thursday or friday...ken...