All four of our springs are identical and a spring-under suspension installation of the new leaf packs is pretty simple. We supported the frame with some big jackstands. Next, pull the tires and loosen the bolts retaining the leaf springs at the spring eyes and then attack the U-bolts. Once they are off, you can support the axle with smaller jackstands. Now pull the old springs and install the new springs. We were able to swap rear springs without pulling the shocks, but you may have to pull the shocks, maybe even the driveshafts, and sometimes brake lines, too.