Brake setup question.

I am quite sure there is no difference between proportioning valves used with power brakes or manual brakes. THe proportioning between the disks in the front and drums in the rear would stay the same.

NOTE: the drum/drum systems do not have a proportioning valve. The lump of metal on the frame is just a distribution block with a switch to activate the break warning light if either the front or rear sides start to leak.