So it isn't a problem?

Yes, the MustangSteve pivot has been installed correctly. But I will check that the pushrod is not in an "over center" condition and triple check the pushrod travel length. Then I'm going to put the MC back in the car and isolate the front brakes then the rear brakes. I hope to learn whether one works while the other doesn't. I guess I could isolate each wheel for that matter.  As we all know, something is definitely wrong - it's just WHAT. I'm about ready to throw out the whole system and send it to a brake shop - LOL. Thanks for hanging in there with me.

GPatrick - Rubber lines in rear to calipers, stainless steel everywhere else - couldn't find SS for rear to caliper. Next try - I figured I would need to isolate front from rear and see what happens. I was hoping someone has had the same problem and had a fix. Thanks for all the suggestions. 

Steve - Bendix Booster I believe a 67' - 69' ford mustang - thick unit with vaccum intake at top - I believe they call it a "banded unit". Will take pictures for bleeder's tomorrow. Please confirm that rear disc bleeders are at top NOT bottom.

Have other's experienced a problem simular to mine? Were solutions found that might be listed in older threads? How would I search for these threads?

I agree that it acts like a bad MC, but it bench bleeds perfectly. MC is mounted to Bendix Booster in correct position, pedal geometry is correct with curved pin in position. I had a combo proportioning pressure differential valve set up originally - had the same result - no pedal. Discovered pressure differential valve had moved toward rear and would not reset due to a bad "o" ring. I went to tee and adjustable valve to see if I could get brakes - no pedal. I'm about ready to go back to single MC with drum brakes! LOL

MC bench bled according to manufacturer instructions. Push rod is maybe .002 from MC piston in resting position. Disc brake bleeders positioned as per Steve's Mustang - rear on top, front at 10 or 11 o'clock position. 3/4" - 7/8" is travel of pedal shaft. Pedal goes to the floor. Haven't tested with engine running, figured I should have solid, maybe low, pedal. Rear pads are up against the rotor - when I apply ebrake they hold rotors firmly. 1" bore reccomendation from Steve's Mustang.  

I overtightened the flare nut on the proporting valve adapter, this crushed part of the inverted flare cone on the female adapter. Needless to say, it will not seal. I believe the adapter is 5/8" x 3/8" - 24 female inverted flare. I cannot find one like the one shown in picture (with holes below the threads). Do you know where I can find this adapter? Thanks

1965 Mustang Coupe, Granada spindles and disc brakes, 620 springs, shelby drop, Lincoln Versailles 9" rear end w/ disc brakes, mid eye leaf springs.
Looking to purchase 17" wheels & tires.
Would like to hear suggestions on backspace, offset and best performing tire size.
Am considering AR Torque Thrust M's in 17x8 all around or should I use 17x7 upfront and 17x8 on rear? Have 1" spacers available if needed.
What are the best tire sizes in front and rear for clearance and performance? What do those of you with set up suggest?
Thanks