ISO: Disc Brake Master Cylinder for 1967 Barracuda

any disc brake master from the late 60's all the way up into the 80's (until they switched to the two bolt style) will work.

just source one with the size piston you want. if you're buying a reman, check and confirm the size when you get it.
So, is there any concern about my current drum brake MC and the piston rod size for upgrade to disc MC???