Thanks Paul, checked your pics out - no luck unfortunately, I think mine is from the eighties, I looked for a freeze plug, but no sign of one on my engine ?
You could try this place and try to crossreference some of the casting part numbers (the part will be cast with a number). It should get you close.<br />Sorry about the link to the competition iBoats, I didn't mean it! (I think this link has been used before anyway)