Brake fluid not comming back to MC

[oldblue1968chevy]

My front brakes are sticking and not comming back to MC

I can crack the bleeder valve to let pressure off.

I can crack open the line from prop. valve to MC to release pressure.

I added power brakes ALONG time ago. At the time it was drum drum power brakes (booster was from a disc brake truck) I swapped all linkage and rod but didnt swap the actual brake pedel. Should I have?

I have new calipers....Mc is about 8 months old Booster is no telling how old possibly original.

Any ideas? Im tired of messing with it just to find out the next day my brakes lock up and im on the side of the road with the hood up. Everybody is giving me crap about it and telling me to take it to somebody...