Lemons cage builder in Southern California?

If you have time and the funds, take it to 7's only racing at the track at Buttonwillow.

http://www.sevensonly.com/Services.html

Why?

Because if you have a problem at tech when you go to the Butt race you will/ should be able to have them fix it first for free.

Besides that, they have fixed dozens of cages last minute for people there, plus they are a pro shop, so they not only know what they are doing, they are familiar with what Lemons wants to see.

But to be sure, print out the "how not to fail tech" pdf.

Another alternative is buy a car already caged... I know of a 2008 prius that needs an updated driveline*

*"updated" driveline available

Where in OC?

Frank Hanrahan at Frank's Fab shop in CM will build you a beautiful cage but you'll pay full freight for it ( Probably 5-6k).  Muffler Mike  at OC Muffler (Placentia and 16th) built the Mazdarita RX7 cage.  He builds a lot of offroad stuff so you'd likely end up with a bunch of extra tubing over your head.  It's been 10 years so you'd need to bring the "How not to fail tech" and rules to remind him of what is currently required.  Aaron Sloman is on The Unofficial Facebook Page of the 24 HoL.  He's in CM and may have suggestions too.  Highly suggest you build with DOM.  The two guys I mentioned will automatically do it.