The registration card for a manufactured home, mobilehome, commercial coach, truck camper, or floating home shall contain all of the following:
The department may modify the form, arrangement, and information appearing on the registration card and may provide for standardization and abbreviations whenever the efficiency of the department will be promoted thereby, except that general delivery or post office boxes shall not be permitted as the address of the registered owner unless there is no other address.
Ca. Health and Saf. Code § 18091.5