Yet Another Bleeding Problem...

Check the rubber hoses, sometimes they get soft and will balloon with pressure.

Ok, you have new hoses but they might have set on the shelf for years. They will start to dry rot. One more thing, I'm thinking you have disk/drums. Have you adjusted them all one more time? I had spongy breaks on my car (pulled the front end apart to rebuild) and bled about 3 times but couldn't get a stiff pedal. I pulled the rear drums and cleaned the dust out then readjusted them just a tad tight. Problem solved!