I was thinking about going spring under for the rear of the blazer. Ive got the 12 leaf pack 63" alcans from ORD and get about 17" of travel from the back. The progressive rate and intrinsic properties of the springs is very nice I just want the truck lower. I have pretty much maxed out the length of the rear shackles to lower it and still want more. Overall goal is lower CoG to go fast in the desert... Bad idea or ????