Since "we" don't live in or under the California laws, the hypothetical questions are obscure. I know what works in MA and it is pretty close to Cali.. but there are differences. And I "think' going to a newer engine with better controls would be a do-able swap. But - you'll need to ask the people in Cali that. To my knowledge also, as long as the components have the CARB number then it should be allowed and pass a smog inspection, a late model take-out should be valid.

Again, I am on the right coast, and only have limited knowledge of the Cali facts.