The best way to bleed is to apply pressure to the res w/o moving the pedal... 5 psi is fine. I put a long, clear plastic line on each bleeder , with the end into a can to catch the fluid..the reason for this is if there is ANY air left in each line/caliper, it will show as an air bubble in the plastic line as the fluid exits each wheel. And make sure you use plenty of fluid, specially on the rears b/c when changing the Master, you are allowing air to enter way up front and it has to travel all the way to the rears ..I see guys say they bled the rears and no air , not knowing the offending air is only 1/2 way down the long line to the rears as they never let it reach the rear..it is still in the line. All the fluid that was originally in the line has to be expelled with new fluid for the air to get out each bleeder, so the rears take a lot of fluid to clear.
Hose constrictions are also possibles..

Here is a trick I would use , with the help of an assistant.
Jack each tire and hand turn the wheel as helper applies/releases brakes w/engine off. It should take your assistant very little foot pressure to lock each wheel and each wheel should release right away as he releases the pedal. Any that don't pass both test are the suspect. If the wheel does not lock, open the bleeder and see if fluid come out there..if it does not release , then open the bleeder w/o pedal pressure and if it then releases, the hose is constricted. If it still locks when bleeder is open, then the caliper piston or wheel cylinder is sticking.
Cars that sit for long periods have mechanical sticking/binding problems all over the place and each wheel has to be addressed.

Just remember this important fact.
The booster has nothing to do with the fluid system..it only AIDS the pedal in exerting more mechanical force...the rod from the pedal to the master is one piece and the vac diaphragm only helps move that rod....applying more pressure to the system...if the pedal goes down w/booster, it is b/c that additional force on the system is causing the fault in the system to create the condition. whereas your foot prssure is not adequate to bring on that condtion....
Check each wheel , one at a time and re-bleed the whole system with a pressure bleeder would be my test to locating the problem.....

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A Dalton