Boat manufacturers measured length around the gunwale, not the centerline. She's 12 ft. or very close to 12 ft. along the gunwale. IF this boat was made at Peshtigo, WI, the HULL ID "51666" indicates she was the 1,666th boat of all models made in the year 1955. How do I know the "5" indicates 1955, you may ask?
1. Thompson Bros. Boat Mfg. Co started using HULL ID's in their watercraft after WWI , circa 1946-47. Watercraft built prior to that time did not have any type of ID on them.
2. They ceased making wooden boats in 1969
3. So this puts this particular wooden boat between 1946-47 and 1969. The "5" was the last digit of the model year, either 1955 or 1965. They did not make any Take-Along models or canvas covered boats in 1965
Therefore she is a 1955 model year boat.
You can look at the brochures on the CD-ROM or flash drive of Thompson brochures, available for purchase at the WCHA store.
Andreas