The problem will be in finding a dual reservoir master cylinder with a bore big enough to displace sufficient fluid to apply those BIG drum brake wheel cylinders. I believe the rear axle has brakes with two wheel cylinders per drum, doesn't it? The Hydrovac has a large, long stroke cylinder that moves a LOT of fluid, and the fluid from the master cylinder at the pedal just acts as a pilot signal to trigger the Hydrovac.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
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