Are you kidding me?! Trespassers, burglars on private property? SHOOT THEIR A$$ES!
You apparently know little about California law. That might fly in Texas. You'll be facing criminal charges until the DA is satisfied that it was a justifiable shooting. Even then, you'll have to deal with the civil suit that they or their families will file against you. Plan to spend at least $100,000 if you have to pull the trigger. Be sure that your life is really in jeopardy. Even Texas is no paradise for what you suggest. Ramos and Campeon are still in jail...and they were just doing their jobs as Border Patrol agents.