My expierence with self-rebuild of brake parts on these old trucks, went terribly bad. I rebuilt some of the wheel cylinders and the MC myself. I wound up having to remove all those big wheels and tires, drums and axels twice. The MC and the WC's failed. I bought new wheel cyls and a new master cylinder. Now, no problems. I got them all at a reasonable price at NAPA and Rockauto. This was a 57 GMC 2 1/2 ton with 8 wheel cylinders.
