I have the car running after it sat for the majority of the last 20 years. New fuel tank and components, new radiator, all new fluids except for brake fluid. I sucked the fluid out of the master cylinder and replaced with new. When I started bleeding at the rear passenger, got a little then it stopped. Same thing at the driver side rear and front passenger. Front driver bled normally. Front passenger brake isn’t working at all based on the rust after a few drives, and I’m guessing the rear drums aren’t working either. Do I have clogged lines? Pulled the front and rear bleeder valves and pumped brakes, still nothing. How hard to replace lines?