i zed mine 4 inches, and took about 2 1/2 inches out of the bottom of the frame, damn it now i want 22's after seein SYCOTICs' truck- bad ass.
on my truck I have top cups which I think are 4" and Iam not running anything on the bottom just bolted it to my lower control arm, and I have had to reinforce my crossmember from dragging it so much, good luck with it man