I have a 1997 f-150 with the 4.6 V-8. I would like to get the Gibson cat-back set-up. Can I get one in San Diego or do I have to go to Laguna Beach?

 

Try going to:
http://www.dmv.ca.gov/
Do a search on mufflers. Basically what it says is you can upgrade your exhaust as long as you have an adequate muffler, and configure it the way Ford has in '97-'01 4.6 trucks. Also, talk to some local shops to make sure. I wanted to delete my mufflers, but it is not leagal, and with the inspections we go through i don't have a chance of getting away with it.
I hope that helps.