Yet Another Bleeding Problem...

wow...I know the pain...are you using a Strange master by any chance????...had similiar problem with the HemiDemon I worked on...changed all but kitchen sink...finally got one of the Mopar alum (knock off) master cyl (1.25) and got great pedal (stiffer than a wedding pecker)...but STILL (as far as I know) fighting a clamping issue on rear...rear wheels off ground..in gear(auto)...and you have to pump/push like crazy...just to get the wheel to stop spinning at idle...brake line pressure good...I say it points to rear calipers(right stuff)...maybe I didn"t adjust their E -brake properly and pads have to far to travel???...but back to spongy pedal....I sent all 3 Strange Master cyl back to them.