I also flip the shackle and flopped the axle on top of the spring.

used an A-body 8 3/4 to tuck 12 rims in the fenders = do the same on the 69 truck.

then used a set of A-body SSM liftbars. they replace the lower shock plate with a square plate welded to a traction bar that clamps to the front segment of the springs, use shims to pre-load axle for launch/hook up.

I removed a leaf or 2 from a set of truck springs for them, they lift the back of the truck 3-4 inches and really plant the tires..you need to dial in the shocks so the don't bottom/extend out.