I think you probably already knew the majority of recomendations would be the obvious ORE that everyone knows and loves.
I have heard of Jeeps-R-Us thats on the canyon road from the 405 to Laguna Beach(I think it has a Laguna address). Now I can not speak on the quality of their work, but I met and talked to the owner and he is a great guy and is very nice. Im sure someone will chime in with actual experience from this location now that I have mentioned it.
SoCal is huge though. Where in particular are you located? If North of LA and TO area, then there's a place in Ventura area thats called "Off Road Werkz" and I know personally that they do great work!