Wellcraft nova year ID

[Slippery When Wet]

Hi all Iam a very proud welly owner and just love the hull,mine spends most of its time on Lake Erie and vacations in northern ontario at our cottage its a little overkill up there but I just hate to leave it home.Iam currently on the scout for a super nice Nova three 26 to 28 ft as my great lakes runner,and brings me to a question of serial numbers,how do I identify the year of the hull from the serial number?