The saga goes on: I've posted before about the on going brake gremlins and so far little success. I have problems with pedal sink and have put in a working booster (7" mine is 8") until some decade the new one I ordered arrives. Now, after bench bleeding the MC, entire system (like 3 times) new rear drums/adjusters, the brakes are worse than before. I cannot get a hard stop. Found the left front 4-piston caliper is rather non-responsive. So thinking trapped air in it we bled the cross-over line on each side finding what looked like some air trapped in it (after repeated system bleeds). Odd as 4-piston calipers, like corvette's, have two bleeders; but mine have a single bleeder so wondering how these calipers can be thoroughly bled if this is an issue. Right caliper is fine, left, the pistons hardly move at all. The pedal isn't spongy though like air typically creates. Pedal is rock hard and stopping is lethargic while having it pressed hard as possible. Any ideas or advice? Thanks.