I went with the aluminum master cylinder (two bolt) conversion that Dr. Diff has, along with spindles from FMJ body . . . used calipers from 5th Ave - so they have the bleeder screw on top (as I have rear mounted calipers), and stainless steel brake lines (again from Dr. Diff.) . . . car is 70 Sport Satellite - manual drum to manual disc. Pedal feel is firm and not too hard, even with the disc's up front. Never had alignment or tire wear issue or driving issue . . . 15x7 "road wheels" - car originally had 14's, but wanted better tire selection (hence 15") - also the 15's are powder coated all way round for use with trim rings - not the FORD all chrome wheel . . . anyhow, yes there are those detractors about using the FMJ spindle - but it works in real world with no issues . . . have 10k miles on the car now ! . . . I am glad I went with the disc brake conversion . . .