Older Old Towns , before diamond head bolts were used in 1920-1922, almost always used #10 screws. The inwales were somewhat larger than the later inwales.
This makes a lot of sense to me. Mine is a 1922 w/o the diamond head bolts. It didn't look like the gunnels were ever taken off of her. There were 4 smaller screws holding down the tips. And those looked pretty consistent.