Most transmission shops will tell you a low price to remove and disassemble your trans then sell you a rebuild once your trans is in pieces. King's in Sodo is the only tranny shop I trust but I'm not sure how much they know about the AW55-50s. I've rebuilt a few and have sent the case halves to Omega Machine in Sacramento to have the bearing holes sleeved. 7 years ago they were the only shop in the country equipped to do this, I don't know if that's changed. Have you done servo cover update? I'll do it for you if you let me borrow the Bimmer for the weekend.