I went to
http://vitalsearch-ca.com/gen/ca/_vitals/cabiygen.htm and put in a basic search using the birth date, female, and the county. This data base sometimes includes the preadoptive name and sometimes it has no record of either. In some cases of adoption there are no first names listed. However, I did find a listing with the last name Hilton.
Here is what I found:
HILTON 1966 07 30 HILTON FEMALE LOS ANGELES 0
PEDROZA 1966 07 30 HILTON FEMALE LOS ANGELES 0
Making an educated guess, and it is only a guess, I would say that the mother's last name was Hilton and the father's last name was Pedroza. PLEASE keep in mind that this is only a place to start your search and is only to be used in reference. It is not fact but an opinion.
Good luck!