My buddy runs Racers Edge Tunning in Downey and got some "good" numbers for my stock 06.He also just finshed a V6 to ShelbyGT500 engine swap which has already been to tuned to close to 500 RWHP and ran high 6's in the 1/8th.
Racers Edge Tuning-Greg
562-545-7001
Don't know how far "north" you want to go, but I can highly recommend B&D Racing in Canoga Park.
Contact Brian at: brian@bdracing.net for an appointment; they also will not BS or rip you on mods you might want to buy in the future. They're a full-race shop and do lots of supercharger, suspension, and gear installs - and they're an authorized dealer and installer for many Mustang parts vendors.
Tell'em Jeff with '05 silver GT vert sent you...maybe I'll get a free lollipop next time I go...lol