Caliper Clearance + Tire Question

I would go with 1973 factory big bolt brake conversion… in fact, that is exactly what I did on my 1972 Duster. 11” disc up front, 10x2.5 drum out back, brake booster, all new lines. Have yet to drive this setup but my opinion is this: Why go with proprietary parts available from only one source, regardless if they are supposed to be better… what happens in a decade if that company went under and now you need brake pads or a caliper?

Also, the factory brakes are supposed to clear factory 14” wheels, but I went ahead and chose 15” wheels since I was planning to run aluminum wheels and not all wheels are created equal I wanted to guarantee clearance.