Jim-
All I can say is
1. Try changing the model number and year and see if you hit it, with or w/o the trailer information/code
2. Try using the first part of the address and see if it takes you to a set of choices of models.
3. I'm thinking now that I might have found this on "iboats Boating Forums"-search their site, although only this one was listed there, but whoever put in the code for this one might give you the code for yours.
4. Go to work on looking for the shop manual using Google or ...?
5. Find a friendly Yamaha mechanic and ask him the address for your motor model.
6. Go to the Yamaha.com site and see what you can find poking around.
Good Luck!
Joe.