I'll vouch for the method described by Truck Tinker. I bled my brand new brake system a couple of days ago using this technique and they firmed up nicely! I used a piece of clear plastic hose so I could watch the air bubbles as they moved from the cylinder to the plastic water bottle. It requires patience and several refills of the master cylinder. Pump 2 or 3 times and watch the bubbles, refill, pump, etc.
Tighten the bleeder valve when the bubbles stop, then go to the next wheel. You may not see a major change in the peddle action until the last wheel. Took me about 90 minutes, but I was in no hurry. Good luck!
