1st Corvette sold to the public has been verified, and it was there all along... the VIN was in a box in the back. Because it wasn't simple to figure out without the VIN, it was set aside for years

Amgwert, along with other founders of the National Corvette Restorers Society, had already tracked down VIN 003 and sent it to Lloyd Miller's shop in Tulsa, Oklahoma, for a full restoration. That led another 1953 Corvette owner to send his car to Miller's shop about 20 years ago.

 It was #1, and no one knew it, and it's history between Chevrolet selling it, and it's arrival at Miller's shop is unknown.

Petersen and Amgwert examined the about 20 years ago, and couldn't reconcile what they saw with any production 1953 Corvette.

Because those alterations didn't make any sense at the time, Petersen figured the car was an anomaly, likely a later production car, and nearly forgot about it. Miller and the owner of the car nearly forgot about it because the owner lost interest and de-prioritized the Corvette's restoration. Miller pushed it to the back of his shop and the two lost touch.

With the work orders seemingly confirming that the car in Miller's shop was 3950 all along, however, Petersen arranged for another viewing, and reached out to the owner, initially just to help "get the car moving along," Petersen said. "The car deserves to be finished up, so let's get to work on it and see if we can prove what it is." His conversations with the owner eventually turned to buying the car and, with a title in hand, he retrieved the Corvette earlier this month.

While emptying out the parts stuffed in the Corvette's trunk, he happened to look under one of the flaps on the bottom of one of the cardboard boxes and found a door jamb VIN plate with a serial number ending in 001.

https://www.hemmings.com/stories/first-1953-chevrolet-corvette-rediscovered/