The 15/16" master worked fine once he put the booster back in.
The manual 15/16" master cylinder wasn't likely to blame, since I also had trouble with the other two manual units that I tried. The 15/16" unit I have on the car NOW with the power booster is an iron unit spec'd for a 75 Dart with power brakes.
Something wierd was happening and I still don't know what is to blame.
