Need Master dual master cylinder...best one?

Ok guys heres the deal. Just got my coronet out of storage and i get in it and no brakes...AGAIN! Same thing as last year after i got it out of storage.Im thinking its the master cyl because it looks like its leaking down the firewall. Now i am still running the suicide master cylinder(single bowl) Its time to upgrade. I dont feel safe driving around with my family in the car anymore. So i need to upgrade to a dual master cyl. Which one do you guys recomend with manual brakes all around. Id like to just say screw it and put all new discs on the front but thats out of the budget...lol......So help me out here guys .And ill need a new proportioning valve too right?...thanks...joe

'66 Coronet w 4 wheel drums? Get a 67-69 Coronet 4 wheel drum M/C which'll b dual bowl. EDIT unhook the rear line from the splitter and cap it (the splitter) w a male inverted flare brass fitting from the "Edelman" fitting bin at your parts house and run the front bowl closest to radiator back to the line you unhooked and connect them w a double female inverted flare Edelman brass fitting