Congratulations, the Old Town canoe with serial number 145811 is a 17 foot long, CS (Common Sense or middle) grade, HW (heavy water) model with open spruce gunwales, ash decks, ash thwarts, ash seats, a keel, and outside stems. It was built between July and October, 1946. The original exterior paint color was dark green. It shipped on November 8th, 1946 to Chicago, Illinois. A scan showing this build record can be found below.
This scan and several hundred thousand more were created with substantial grants from the Wooden Canoe Heritage Association (WCHA) and others as you probably know well. A description of the project to preserve these records is available at
http://www.wcha.org/catalogs/old-town/records/ if you want more details. I hope that you will donate, join or renew your membership to the WCHA so that services like this can continue. See
https://www.woodencanoe.org/about to learn more about the WCHA and
https://www.woodencanoe.org/shop to donate or join.
It is also possible that you could have another number or manufacturer if this description doesn't match the canoe. Feel free to reply here if you have any other questions.
Benson