Hy Panman, a lot of the parts are the same between the 3/4 ton and 1 ton brake systems, some one tons have 12" front and rear brakes, and some have 12" front and 14" rear brakes, both have 1 1/8" master cylinders. Corvette master cylinders are for disc/disc applications, so you will need 10 p.s.i. residual pressure valves for each of your drum brake circuits. In short the systems designed for a 3/4 ton truck should work, but I would not go smaller than a 1 1/8" bore master cylinder, hope that helps.
