I bought a deluxe lowering kit for my 54 Belair from Jamco. I installed the front coils without much trouble and moved to the rear leafs. I installed the front bolt and brought the spring up to the axle perch. The alignment hole is about an inch off. It is forward of the pin. I fiddled with it for a while and it is off by about the same margin at the rear shackles. I must be doing something wrong..... Never installed leafs before I need some guidance!!
Put a 2X4 between the frame and the spring, then slowly jack up the spring to flatten it untill the holes line up. Keep your face away, things can slip.