so you replaced the rear cylinders, have new pads (pads are on the front, so new rear shoes too?), and a new master cylinder.
did you bleed the system properly?
did you adjust the rear brakes?

 

yes new shoes and I bled rear diver , rear pass, front pass, front driver then the load valve in the back. Im no longer losing fluid and all the lines have been checked for leaks. When I drive a good long ways and slow down the brake pedal gos to the foor, but if I stop at redlights or traffic it gets stiff other times its perfict. So far its an improvement from lastweek. I'd still like to fix it 100%. Only thing I didn't touch is the booster.