Rattletrap,
A lowering block would work on an axle that is OVER the leaf spring, as in the rear axle of these trucks. It is a chunk of iron or steel that has provisions for the centerbolt cast in it...it is a spacer! You stick it between your springs and rearend and it lowers the truck. The front axle rides UNDER the spring pack. You could put a lowering block here, but it would become a "raising" block, making the front end higher.
Stuart.
