Certified Auto in SLO is fantastic, but I didn't go there. I sent my truck to AMG Performance in fremont. They came highly recommended from a friend for transmission rebuilds and big projects. C.A.R was going to be my backup because they changed out my ignition when i broke a key in it last year and were FANTASTIC. I cannot recommend anyone else in SLO aside from them.
On a sort-of unrelated note, some friends of mine and club alumni have started their own fab shop, Trail Tested Manufacturing in Templeton. If you are looking for any offroad work done I would suggest giving them a try.
Link to their website, they are a brand new company so they don't have much on there quite yet
Trail Tested Manufacturing