Anyone know if the 67-69 disc/drum master is interchangeable with the 70-74 master? I have a master for a 70 will I be able to use it on my 69 Cutlass? Is the only difference between the 2 the reservoir style?

 

The only thing that matters functionally is the piston bore. If they are the same bore, you can interchange them. Power disc brake M/Cs for 1967-72 should all be 1 1/8" bore.

 

Thanks Joe!
That’s what I was thinking. Yes, they are both 1-1/8” for power brakes.