Re: What Mercruiser do I have?
All the one's I got have the numbers stamped on a flat hmmmm about 1" by 3(?) inches at the very top of the out drive as it goes horizontal to the gimble (clam shell). If yours hasn't been painted 5 times there may be a Mercurzer decal over it. There is also usually a metal tag in the boat on the left side where the gunwal meets the beginning of the transom that says mercruzer and the number.
But I don't know why you would think it is the original out drive!!!
Most manuals I found cover a WIDE spectrum of all models.
Grzzzz