The Shelby in question is one of the few prototype Mustangs still in existence. EXP stands for experimental. The car featured the first use in a Mustang of fuel injection, special disc brakes, and an independent rear suspension.
It became a sort of pet project for Shelby chief engineer Fred Goodell, with plenty of input from Carroll Shelby himself. The platform paved the way for many modern enhancements the Mustang saw from 1967 up until today. Being saved from the crusher, it was thought to be lost in history until a keen collector picked it up and gave it a full restoration.
Unfortunately, the owner values this car so high, even the $1.8 million bid didn’t reach the reserve price. For now, it remains tucked away in a garage somewhere waiting for its next go at the auction block.