Ford promised that a very special GT500 would go up for sale this past weekend at the annual Scottsdale Barrett-Jackson auction, and they did not disappoint. For the first time ever, Ford auctioned off a true piece of history, the 2013 Shelby GT500 “durability prototype.” This test car was run hard, and run often, to help Ford tweak and tune the 650 horsepower 2013 GT500 on the track and the street. And Ford auctioned it off to the highest bidder.

Just how high was the final bid when the gavel came down? A cool $300,000, all of which went to the Juvenile Diabetes Research Foundation.

We already covered just what this one-of-a-kind prototype car entailed, but for the uninitiated, pay attention. This was one of Ford’s test mules, complete with the 650 horsepower 5.8 liter supercharged V8. This special car saw speeds in excess of 200 MPH, and was fitted with all sorts of camouflage, a roll cage, and testing equipment to ensure that when it hits the streets this spring, the 2013 Shelby GT500 is ready for the road.

Unlike most of the polished and cleaned machines that went up for auction, the 2013 GT500 prototype went on to the auction block wearing mis-matching bumpers, dangling diagnostic equipment, and the unfortunate bugs that wound up squished on the front fascia. The SVT team even signed the trunk lid, a very special memento to a very special car.

Special to the tune of $300,000, which wasn’t even the most paid for a Mustang this past weekend. That honor goes to a barn-find 1965 Shelby GT-350, which brought in $350,000. That Shelby name carries a price premium, that’s for sure.