The two new charts in the WCHA Knowledgebase show the serial numbers by date for the period from 1905 to 1965 at http://forums.wcha.org/attachment.php?attachmentid=24291&d=1360203686 when the first fiberglass canoes were introduced and to 1995 at http://forums.wcha.org/attachment.php?attachmentid=24292&d=1360203686 when they stopped recording the build record information on paper cards.
Benson
Benson