Did it turn out to be an ex rental saw? That's what it looks like in the pics. The top cover looks like it's had the paint marker numbers removed, and the clutch cover is missing paint right above and below the bar nuts from using a regular socket instead of a scrench, HD style. The numbers that are scribed into the tank handle looks like they've been sanded away. The one for sale here looks like it's had the same treatment as yours, if you look closely.I bought a saw from him back in June. It was not what he made it out to be but not bad enough to send it back.
I currently have three ex HD saws, and used to have one more, and they all look like this.
I also see that he claimed yours only had 3 tanks on it. It must be 3 tanks while idling on the pavement with someone sitting on top of it, with the bottom looking like it does. Don't get me wrong, your saw is great and I love those HD deals, but it's not what he told you it was.