As stated above Brian Crall in San Ramon would be a good place to have a PPI. I have taken his advice before and was always glad I did. Kept me away from the bad and always pointed me to the good.
Might try Dino Motors in San Mateo, talk to Johannes Huwyler, another good source of information.
There is another shop up in Marin County, but I think that may be too far for your purposes.