[Verne_Frantz]

Yes Mark,
In my post I mentioned "US production". I don't recall if my production totals listed Canadian or Export. Some years they do; some years they don't. In any case, I'm quite certain it's a very late car, although I'm surprised the plant only built 96,000 full size cars that year. (first car was 100001). But since this car is basically in "as found" condition, and sounds like it had a hard life, I doubt there's been any horesplay with the tags.
I would suggest a follow-up through the '65-'66 club for clues as to which 396 was originally installed. If it turns out to be an L-78 car..........oh boy! (check the redline on the tach, for starters)
Verne.