My personal preference would be to avoid having any visible documentation number. It isn't necessary and it adds to visual clutter. Just get 3" high registration numbers at your local boat store and stick them to the inside of the aft cabin closet. Slap some resin over them and call it quits. See photo which shows a portion of my documentation number located inside the aft cabin closet.

This is from USCG form CG-1258 (REV. 06/04)

[B]VESSEL MARKING INSTRUCTIONS[/B]
Every documented vessel must be marked with its official number, name and hailing port. A Certificate of Documentation is not valid for operation of the vessel until the vessel is marked in accordance with the prescribed regulations contained in 46 CFR 67.120.

[B]OFFICIAL NUMBERS[/B]: The official number shown on the Certificate of Documentation, preceded by the abbreviation "NO" [B]must[/B] be marked in block-type Arabic numerals of at least 3 inches in height on some [B]clearly visible interior structural part of the hull[/B]. The number must be [B]permanently affixed[/B] so that alteration, removal or replacement would be obvious and cause some scarring or damage to the surrounding hull area.

[B]NAME AND HAILING PORT[/B]: For Recreational vessels the name and hailing port must marked together on some clearly visible exterior part of the hull. For Commercial vessels the name must be marked pm each bow and the vessel name and hailing port must also be marked on the stern. The markings may be made by the use of any means and materials that result in durable markings. All must be at least 4 inches in height, made in clearly legible letters o the Latin alphabet or Arabic or Roman numerals. A vessel’s Hailing Port marking must include BOTH a place (city) and the state, territory or possession where the place (city) is located. Only the state, territory
or possession maybe abbreviated unless the city is a commonly known abbreviation, such as N.Y., N.Y.

My documentation numbers are 3" stick on vinyl, placed on the inside of the hull in the port lazerette next to the coolant reservoir. I over sprayed the numbers with 3M M77 spray adhesive to make the installation permanent.

Marc Nachman
Whispering Eye
2004 Catalina 36 MkII #2201
SM/RF WK M35B

The dealer placed mine on a thin fiberglass rectangle, glassed over, on the inside of the hull inside the portside cockpit locker. I don't have a pic handy. I'd say the numbers are close to the legal size. Completely out of the way, but I'd say they're still legal.

My numbers are carved into a wood plaque that is placed inside the v-berth aft wall. They are indeed 3" tall. They are very visible - but I don't notice them unless I am lying in the v-berth.

Mine are in the locker under the cushions on the port side of the cabin. Plain old plastic numbers covered over with a layer of fiberglass. No one ever checks these numbers to my knowledge anyway.

It’s been a month since SV Lori Lee’s original post but here's mine…

Mine are actually etched on one of the bigger cross-pieces of fiberglass in the bilge. Completely out-of-the way, and a great place (IMHO) to put them! I'm not near her right now but I'll post a photos over the weekend / next week if folks are interested.

Can't you find room under the top of your nav station? C'mon. Under your V berth or aft cabin somewhere? 3 inch high shouldn't be a real challernge...

Mine are under the V berth lots of room for 3 inch