I have the original master cylinder and booster diaphragm on my 69 SS and I just noticed a slight hiss after turning the car off. Anyone know where I can have mine rebuilt and Cadmium plated at? I would also by one if it was a real Delco that was plated for a fair price. I would like to keep mine since it appears to be actuall master combo that came on the car. Anyone know who has good prices on these? Mine is black and I don't know if it was always black or whether it just got painted like everything else did at some point. I like how the plated ones look. Anyone know how they are supposed to look?

The originals were gold cad plated. Not all had a stamp. Some times the stamp would end up upside down when the booster halves were assembled.
Check to see if your check valve is what's leaking.

Thanks Robert! I will check that. I appreciate the info.