Dual Master Cylinder

The 36338 NAPA master cylinder is almost, but not yet, extinct.
RockAuto is selling the last of them at $11.22 ea under the United name and has less than a dozen available at that closeout price.

Note the application was originally for 71 to 74's with manual front disc brakes/drum back brakes since this cylinder has a small bore 15/16 dia to reduce pedal effort to reasonable levels.....the result is a 40% longer stroke to get the brakes locked up.

I installed the cylinder, without any push rod modifications, in my 65 Dart fitted with Scarebird front disc brake setup & maintained the 9 inch rear drum brakes. I find the longer stroke gives better control on braking pressure on wet & icy roads when stopping. No proportioning valve was used. The front line goes down to the original splitter while the rear line heads straight back to the rear splitter on the rear axle housing.