Take a rubbing of the numbers, they should show up quite clearly. Position a piece of paper over the numbers, and lightly rub a pencil over the entire area. The pencil will darken all areas except the recesses forming the numbers. Its a simple technique to master. I find that using a dull-pointed pencil and rubbing at a 45-degree angle produces the best results.
The hull identification number (HIN) is a twelve-digit number required to be located on the transom within 2" of the shear and 2" of the starboard hull side, or on the starboard hull side, within 2" of the shear and 2" of the transom. Note that the “sugar-scoop” swim platform added to many Freedom 36’s covers the original HIN.
The format pre-84 should be XXX9999M99X. The first three digits, letters, are the Coast Guard assigned manufacturer identification code (MIC). The next five digits, letters or numbers, are the unique hull number assigned by the builder. Many builders, including TPI and Freedom, use the first two of these digits to identify the model and the last three to indicate the sequential number for the hull. The letter “M” is a place holder. The next two digits are the model year. The last digit, a letter assigned by the builder, represents the month the boat was either molded or completed.
As of August 1, 1984, the format changed slightly to become XXX99999X999. The first three digits are the Coast Guard assigned manufacturer identification code. The next five digits are the unique number assigned by the builder. The next letter represents the month the boat was molded followed by the last digit of the year it was molded. The last two digits are the model year.
A two letter country designation is permitted as prefix, separated by a dash from the HIN. Additional builder-assigned digits may be added at the end separated from the HIN by a dash. A plan requiring additional digits, including a “check-sum” was suggested but not implemented.
In 1984, builders were also required to put a second HIN somewhere else in the boat. This earned the nicknamed the “hidden HIN,” but hidden is a subjective term. The hidden HIN can be found under the companionway seahood on many TPI built sailboats. Other areas to look are inside the propane locker, in the gutter of one of the molded cockpit hatches, or in the molded hatch to the engine space.
Note that only the original builder may assign and afix the HIN to a new boat, and approval of the Commandant of the Coast Guard is required to change an existing HIN.