You may be right about this, unfortunately. But I've heard so many conflicting stories over the years here in CA (including from mechanics, DMV officials, and CHPs), that I've learned to take everything I read/hear with a grain of salt. But I do appreciate your trying to spare me all that work for nothing.
I don't scare-off easily though, and I'm determined to pull this conversion off, if it means finding a loop-hole, or even (eventually) changing the law itself. (I looked into this conversion back in 1990, and I got numerous conflicting tales from various officials, mechanics, etc. What I have yet to lay my hands on is something cut and dry in writing. If you know of such information you can cite, please do so, as I have alot of legal research ahead of me.) In years past, any radical engine modifications (including non-factory turbo-chargers) in CA have required the vehicle owner to perform some rigorous testing (including a dynomometer) to prove its compliance.
Things are changing now, and new options are being considered. (Retrofits involving cleaner-burning engines could be considered in future. They already are to some extent, in various forms. "Governator" Schwartzeneggar is already proposing a bill to retrofit older diesel engines.) Maybe the foilks in Sacramento just need a little persuation?
...Dave