Proportioning Valve

I cannot tell from your photo, do you have the calipers installed so that the brake line and bleeder are 'at top?' Do you have a good hard pedal? Or does it go down "all the way" (or most the way?)

With no proportioning valve, normally "one end" of the car will lock up way before the other, a prop valve has nothing to do with whether it "stops at all" or how hard you push or how far the pedal goes.

You can buy aftermarket adjustable valves, and add them into the system, leaving the original distribution block/ warning switch in place