Well with the advice from Tom Arnold and the rest of You fine folks on this site I tore down the rear end on the 644 today and found that I purchased someone else's headache. After finding silicone in place of a gasket I knew it would be rough going but I continued on anyway and found one sorry case of pure neglect on the former owner/owners part. With all of the worn out parts would it be in My best interest to fix or find another rear end altogether? I attached some pictures and let Me warn You it isn't pretty, You may want to keep all of those weak of heart and small children away from the computer while viewing.