I would obtain whatever fittings you need to block off the system at various points. Then see how hard it gets with the rear plugged off,etc
I can only tell you my "example." Before I tore my car apart, I used the factory 67 non power drum master--just poked holes in the residual valves. The front brakes are common 73/74 Duster/ demon, the rears are Lincoln Versailles rear axle and factory Linc disc brakes. I dont remember off hand how far the master goes, maybe ? 20-30% of travel and then it is just plain rock hard. I could lock them up easy at 70. My legs are not that strong anymore, I'm 73 now
