I went to an auction last weekend, bought some boats and wished I could have taken more. one is a Penn Yan Cartopper WXH 516552 - according to the Dragonfly site "Two or three letters followed by 3 or 5 digits is typical," and "Dating: Sometimes (apparently only in the second half of any given decade) the first two digits of the serial number are the year built," so- is 1951 the date? overall, its not too bad, it has been fiberglassed, but very good ribs, a crack in an outwale and some rodent damage, its missing the oar lock sockets and one seat bracket. I did get all the part for the floor rack. over all, a good project boat. does anyone know what the waterproofing Penn Yan used on the canvas was. An old catalog refers to it as covered in "8 oz pyroxylin processed canvas". and also brought home a couple Keuka trout boats a one seater -it has also been glassed and longer one, a real project boat - some work was already done to stabilize it, and most of the parts that have been removed were saved. There is lots to be done, but if I can handle it, I should end up with a beautiful rowing boat out of this hull.