Backing plate
I converted my 10 inch drums on the 9 inch housing to an 11 inch vented drum from a 72 LTD. The backing plates line right up. I used the stock Vega disc brakes in the front after they were redrilled by Moser to a 4 1/2 Ford pattern to facilitate five lugs. They had to be 4 1/2 due to the design of the rotors. Ran a master cylinder for a 69 Camaro with disc brakes. Had a proportioning valve to adjust the car for better braking but never installed it. The brakes work great and don't fade or pull. A lot of Ford parts are interchangeable, you just have to see what works. Hope this will help you.