Re: merc 7.5
A few years matter most when there are significant changes in the models. It can make a big difference in cost and avialability of parts. I bought a 1976 Merc 200 on eBay but the seller gave me the wrong serial number and had advertised it as a 1978, which matched the number he gave me. They made several changes in ignition and electric starting in those two years and it has cost me a good bit more to bring this engine up to snuff than it would have if it was a 1978. Still it is a good motor and yes, as long as it runs that is the most important thing. Caveat emptor, and check the serial numbers. Hard to do much when a seller just lies to you, though!