How do you smog one of these in CA? Can you go to a newer/larger engine in and older car, or do you just have to sorta fake it and hope you don't get caught?

I beleive the "smog" has to be for whichever is newer -the car's build date or the motors build date. So.. Stuff a 1995 911 motor in a 1971 911, and you need to meet 1995 emissions standards. Stuff a 1971 motor in a 1995 911, and well, good luck ;)

In CA, a newer motor is OK, older , no!