Date setting should be described in your manual but if you do not have it, then you can get another copy by going to their web site "modaine.com".
Select "after sales service" and a list of instructions appear. This list claims to cover all the watches they make but doesn't include the model number you quoted. Could it be that the number was the serial number for the watch?
The manual list is not too long, so it should be possible to down load the most likely looking candidates.