I DO see that this inquiry is a couple of months old.... I recently lowered my 68 suburban with two inch lowering blocks from CPP. The truck arms suspensions have the springs and shocks all tied to the truck arms, so the only item you need other than the blocks and u-bolt kit, is one of CPPs adjustable track bars. These bars adjust like a big'ol turnbuckle, so very easy to use. Two inches is the tallest blocks CPP shows offering, but the u-bolts for these are at least an inch too long...