Well, I know it has been a while, but the front disc brake swap is finally finished on the 63. It took a while, lots of brake fluid, some cursing, eye rolling from the wife and a bunch of head scratching, but it is don at last. I never did trip the prop valve. I must have sucked some air into the master cylinder at some point, because I was getting solid fluid at all the bleeders, and the pedal was still horrible. I re-benchbled the MC, and the pedal was still not too great, so I looked at the cleavis rod that connects to the pedal and sure enough after adjusting it back towards the rear to hook to the pedal it was rock hard. Now with the discs on the front and new parts in the back, she stops VERY well. I almost put myself through the windshield on the test drive. Thanks to everybody for the help and advice.