M_Boats: My new (to me) M15

Hi all, I bought a very nice M15 in Michigan last week. The former owner and I were trying to determine its vintage from the hull number stamped in the starboard transom. Can any of you break down the exact meaning of this number: MM P 15500D92. Thanks, Dan Mostue -- Using Opera's revolutionary e-mail client: http://www.opera.com/mail/