You are essentially cutting off the front clip and raising it up so that the bottom of the crossmember is level with the bottom of the frame instead of 3" lower. It will allow you to lay out flat, not drag off your control arms, and be pretty damn low with no BD, or minimize the BD you need to lay rocker.
Keep in mind, you will be losing hood clearance, and your steering linkage from the firewall to steering box will all need to be custom. You have to drop the front frame horns the amount of the Z + the amount of BD (if u do a BD) so your fenders line up.
Good pics here:
http://www.nfamusairsuspension.com/page13.htm