When I pulled the brake housing off, the  thrust bearing was indeed shredded.  Unfortunately, the end of the bull pinion shaft acts as the race for the bearing.  It is scored pretty bad.  

A new bull pinion is not available anymore.  I ordered a used one for over $500 from a source I found on the internet and got it today.   It was scored worse than the one I was trying to replace.  I'm going to return it Monday and start over.

I'm assuming the end of the bull pinion should be very smooth, or else I'm wasting my time trying to replace it.  I am thinking that if I put a new thrust bearing against a rough face on the pinion, it will just get shredded again.   

Has anyone faced this problem?  What are my chances of fining a good used bull pinion shaft.  I haven't taken the other side off yet, and am afraid of what I'll find.