[Bigdav160]

Non-power assisted brakes will have a smaller bore than power assisted brakes to give more hydraulic advantage at the expense of slightly longer travel. Like 1" vs a 1 1/8" or 1 1/4"

A hydro-boosted setup you could probably get away with a larger bore just because of how much assist the hydroboost gives.

I am using my OE 1972 3/4 ton MC on my hydroboost.