SSV151 or SSV167
take a look here under All About Glastrons ,
The Years - factory images & more http://www.classicglastron.com/
i had a glastron carlson cv21 with barkley jet and upgraded 450hp olds for couple of years and they did help me a lot on this page to get it back to original. http://www.angelfire.com/super2/powertoys/boat.html
michael
If it's a Glastron then it'll be an SSV 153 (the SSV 151 had an open bow). However from the picture I can't see the side profile to see if it has the "sharks tooth" moulded towards the stern. If it doesn't have this its a Spirit (made from the Glastron moulds) by either Roger Clarke Marine or latterly Dave Picton at Picton Boats.