The best rigs I have found for big spots are the old style Castaic Craw and the Castaic Threadfin Shad. I use the Craw when fishing around cover and in shallow water(color hasn't seemed to matter). I use the Threadfin for casting in open water and along shorlines. For deep water, I carolina rig the Threadfin with a 6-8 foot leader and whatever size weight I need to get down to depth quickly. I have caught dozens of spots over 5 pounds with these lures, including 2 seven pound spots! The only 2 over 5 I have caught that weren't caught using the Castaics were on handcarved topwater lures.
Castaic Craws are getting VERY hard to find, so if you find a source, PLEASE share it!
Hope this has helped, JT