[Mike C]

Thanks for those links Frank. They do not show a 302 powered 69 Camaro to look up the disc/drum Z/28 master. They show two different Corvette masters, a 1 1/8" for power brakes and a 1" for manual brakes.

For the 80 Trans Am, they show a 1" bore for manual brakes. Not sure on the depth of pushrod hole on power vs. manual mc, but on my '69 Camaro I have a Z/28 power disc master actuated manually with no problems, so there appears to be several options.