Update:
I used the old pressure plate(cleaned up and polished with emery cloth) and the disk out of my 50. I compared the disk to a new one at Chevy Duty and saw no appreciable wear. It works fine, I'm pleased.
The carrier bearing on the front drive shaft was ok, but the rubber support around it was history. Jim Carter carries the support, Chevy Duty doesn't. The trick is to install the rubber support in the bearing carrier and then install the drive shaft with carrier bearing, it won't go together any other way.
I didn't have access to a cherry picker, so I pulled the tranny on a floor jack. Installation was harder, it fell off the jack 3 times. I finally set a 2x8 on step ladders just outside the doors of the truck, running thru the cab and hung a come a long from an eye bolt thru the 2x8. It helped a lot. I wasn't able to see the end play describe above so I'm assuming that the thrust bearing is ok. The truck drives much better, the only problem is a slight wheee sound when I engage the clutch from a stop. it sounds like the throw out bearing (new) spinning up. It only makes the sound pulling away from a stop, not when you are shifting.
