Originally Posted by jerry gollnick

So I looked up this master cylinder and it can be had in different bore diameters. My car is a HD brake drum option car and the wheel cylinders are all stock diameter. I believe the original bore diameter of the master cylinder was 1 inch , so my assumption is that i would use a 1 inch bore diameter with the dual master cylinder. The mounting for the original master cylinder used three bolts. The Camaro dual master cylinder from 67 thru 69 were a two bolt mount. I can machine a three to two bolt mount. I think someone on this board must have done this before, is this what you did and how did it work?