Need help identifying the age of my Grumman canoe

Advice
#1

Hello all.

Can someone help me identify the age of my Grumman canoe? I read they sometimes have a HID located near the stern of the boat but I have been unable to find it.
I have also emailed the marathon Boat Co but have not heard back from them yet.
It is a 17’ square back.

Please click here for photos.

Thanks,
Shawn

#2

May very well be pre HIN number days
Think they started using them in 72
This plate looks exactly like my 68 Grumman

#3

Thanks! Does yours say Marathon NY?

#4

I don’t have it anymore but yes it was made in Marathon NY