proportioning valve??

Something you might want to consider is leaving your stock 60 % front 40 % prop valve way better brakes than changing it out. Ive done this on my last 5 conversions ive done. Unbeliavable brakes. My 68 FRANKENDART 360 FI 518 OD has this set up manual disc. The harder you push the farther you want to go through the windshield.