brakes not working right

I have a '73ish dodge swinger I'm trying to get on the road. New brakes, shoes master cylinder, wheel cylinders. I can't get them to work properly. They work sometimes, then they barely work, and sometimes, they lock on. Bled the master cylinder before installing, bled the wheel cylinders repeatedly. Adjusted the brakes twice, and they seemed to improve for a while, before going back to part time. Any ideas?