I went to Panteraplace.com and there is a very good article on replacing the rear busings and bearings, but Mike went to a Timken tapered bearing...you have to change the seal but it appears that is the only change. I think I will email Mike and see if he has the part numbers...there is a link in his article for the Timken site but it no longer works.
http://www.panteraplace.com/page87.htm
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