[wrightz28]

I think your primary piston cup in the master dried up a bit and quit after sitting. If you had to add that much fluid, it almost confirms it along with the pedal travel. If it isn't visually leaking from between the master cyl. and booster, than chances are you have a vacuum booster loaded with the "lost" brake fluid. You could pull the vacuum hose off and check for signs of fluid to verify.