Dr Diff Master cylinder

You can buy just the adapter plate ~$30 ebay. I did, and mounted a 99 Breeze MC ABS 7/8" bore on my 64 Valiant as manual brakes, using the original pedal rod. Brake pedal wound up in the same place. The MC shown looks like the one for late 1980's Dodge trucks, which many here use. You might buy it cheaper locally or ebay/amazon. Avoid 2000+ MC's since most changed to bubble-flare ports.