Mc ??

I did some searching, the MC that came from the GM car that uses my calipers has a MC bore of .875 or 7/8 (22mm). The 13/16 bore is 21MM and both have pwr brakes, the 75 dart has a bore of 15/16 or 24mm also the dart with man brakes uses a 4 bolt mounting position, so i was hopeing to use the adaptor and go with the K car MC if it will work since it seems to be the closest match as far as bore size..