I'd suggest changing both wheel cylinders for brand new (not rebuilt) ones, and also the flex lines. It sounds like there's something sticking on the driver's side that's allowing the passenger's brake to get all the fluid pressure. The most likely suspect is the flex line. The problem is most likely to be a restriction opposite the side that's locking up. I'd concentrate on finding out why the driver's side isn't working- - - - -not wasting any more time looking at a brake that's obviously doing what it's supposed to be doing.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!