The pinion angle is my biggest concern - I think I'd have to shim it for sure. I don't think I'd be lowering it enough to have to re-weld the perches though. Also, the springs are the XHD Mopar Performance springs.

Does anyone know where to get good solid-steel lowering blocks with the correct U-bolts? I checked Summit, Jegs, Mancini Racing and haven't really found the right set for a '71 B.