A few more things...
With the hose connected to the slave and the bleed port closed - the new slave on the car - you get no pedal resistance right? Just goes to the floor?
With the hose disconnected from the slave and no tricks to rty to open the dry break going on, do you get pedal resistance? It should stop pretty quickly if the master cylinder is good. As basically, you're trying to push fluid against a closed devise; the hose with closed dry break on the end. If it goes to the floor you either have shitloads of air in the master cylinder, or it is shot.