I live in T-Town and have personal experience with and full confidence in these independents:
1. Dan Knowles Foreign Auto Clinic, 424 St Helens Ave, Tacoma, 98402 (253-272-0062)
2. Lloyd and Wilson, 631 Baker St, Tacoma, 98402 (253-627-1514)
3. Rolf's, 3121 20th St, Fife--they also have a shop in Lakewood, south of Tacoma (253-248-1080)
So, depending on where you live or work, whichever is more conveniently located should be able to do a good job for you.
Let me know if you need any more info. Lots of good car stuff going on in Tacoma. Regular get-togethers at Griot's Garage, active BMW and MB clubs and a great track nearby (Pacific Raceways) for track days and vintage car racing.
Bill