i too have master cylinder problems on my chevy c60 truck. i have not found a replacement for it as it is 2 different sizes the clutch is 1 1/8 " but the brake is 1 1/4 i can fine dual 1 1/8 and dual 1 1/4 but not the 2 together does any one know if i go with one of the single sizes will it be a problem one way or the other will the 1 1/4 overwelm the clutch or will the 1 1/8 not be enough for the brakes ???