Superlift offers its standard block kit for the rear with its 6-inch suspension, or you can opt for full replacement leaves to eliminate any block but the factory one.This four-leaf (plus an overload leaf) had a lot of arch but seemed like it had a good amount of movement in it. Dennis Gregory and Ritterbush lifted the spring into place for the front spring eye, but it took a little massaging to get the rear spring eye into the shackle. We'll see how well it flexes when we get out to test the truck.