I have never had a problem bleeding brakes and I leave the delay valve alone. Unless you replaced the delay valve leave it alone. All this is muddying the water. The position of the rear end doesn't matter unless you are gravity bleeding.

I would buy a new Master, $25, and bleed the brakes again.

Just on a chance, make sure your calipers' bleeders are pointing up. I have seen them reverse and the bleeders do not work correctly.