I just took a trip to hog ring city here. There was probably a couple hundred hog rings holding the old upholstery tight to the seat frames, and each one had to come off with the twist of the pliers. Once all the upholstery, foam, and misc. covers are stripped off the top and bottom seat frames, give them a good cleaning. The back bolts to the bottom frame via the hinge arms, which may or may not actually hinge.