Darrell,
Im learning a lot regarding Ontario plates on military vehicles. Various sites seem to indicate that the F suffix plates started in 41, and one site claims they were in use until 68.
This site has various colour images of F plates:
https://ericsplates.weebly.com/wanted.html
The following page has some excellent images of Vickers Mk VIb in 1941, and includes the quote:
Nice photos of the Ontario F suffix plates on the military vehicles. They look to be the '41 base. I'm pretty sure that was the first year for the F suffix plates, and they were issued in '42 and '43, anually. Then in '45 they came out with permanent white on brown plates, which were used up to 1968. Since then the Dept of Defense has taken over registry of all military vehicles, with plates marked CANADA.
Scroll close to the bottom of the page:
https://wwiijeepparts.com/Archives/1...ensePlate.html