Master cylinder question

Dr Diff sells a 2-bolt MC for 1980's Dodge trucks, both standard and with a custom smaller bore (higher price, 15/16"D I recall), plus a 2 to 4 bolt adapter plate. On ebay I recall but linked here many times. I use an ABS MC from a late 1990's Breeze/Stratus/Cirrus w/ 7/8" bore as manual brakes in my 1964 Valiant. The Valiant pedal rod fit the piston (w/ new rubber bushing) and the pedal wound up in the same place (search post for photos).