the only way you can truly verify that your car is indeed a california special is to get a "marti report" from kevin marti. the VINs listed in the registry can not be guaranteed to have been built with the california special option. i believe in the next registry book there will be a way to determine if your particular car has indeed been confirmed as a true california special by a marti report.
another way to determine this is to order a CAC report directly from ford (also listed in "VIN report" to the left on this page). it will take a little longer than the marti report but it's free. it's also not as detailed. my CAC report does not list my car as a california special, but the marti report does. some of the reports do list the california special option and some don't. i suggest getting the marti report, it is full of information and well worth the money. i hope this helps!
tom