"making a HIN-quiry"
Note that the HIN system came into being in the early 70's, and (reportedly) different builders adopted it over different years/months.
Interesting story: a friend of our just had his '68 Ericson totally rebuilt and it just went back into the water yesterday. The builder actually uses a "reverse lettering" Dymo printer to generate a proper molded-in HIN on the proper place on the transom. On this boat, an Oregon title number was assigned and duly imprinted before the new LPU paint job was done.
I know several sailors who have built boats and any time a boat goes into the Oregon Marine Board db, a local LEO has to come to the boatyard or your driveway and confirm the existence and ownership! Over the years this has resulted in some great conversations with bemused deputies or troopers who liked something cheerful and non-life-threatening in their daily work schedule.
On a boat from the 80's or later, that HIN should be in plain sight on the upper starb. stern area.
Matter of fact, any thorough survey will include a page with a pencil rubbing of that code.
Cheers,
Loren
ps; that classic E-30 was launched yesterday at the same yard where Mark has his boat. The yard owner commented on the number of EY boats in the last week, given that just days ago he launched yet another O-34.