Hmmm… maybe you’re right!
The site World of Monkey Island shows some original art from Bill Tiller
http://www.worldofmi.com//thegames/monkey3/index.php
look at this:
So there it is definitely a 6.
But if you play the game, (or watch the image I posted before) you see an angle and not a curve as the top part of the second digit. Maybe that was a choice to make more difficult to catch the exact year for a fictional world of pirates… It isn’t better to be vague and dreamy? 