6 Remove all of the retaining nuts except for one of the top most nuts. Depending upon if the center section has been removed before, you might find copper sealing washers at the base of the studs. These will need to be pried off of the studs as well. Oh, and if you can access the bottom two most studs with a socket, as shown, you indeed have an 8-inch rear and not a 9-inch. The 9-inch requires a box-end wrench for access to these two retaining nuts.