I'll have to disagree with the above comment regarding "the Beast" sun shell in comparison to others I have found "the Beast" to perform just as well if not better then other aftermarket sun shells on the market today. Even though "the Beast" can be a little more expensive... in my experience (over 20 years rebuilding GM transmissions" it is the best on the market.
I buy most of my rebuild parts from
www.gmtransmissionparts.com so here is the link to their part:
http://www.gmtransmissionparts.com/T...4L60E-1011.htm
I hope this helps!!