One lucky buyer will take home this rare hand built 1969 Ford Mustang Boss 429 Fastback prototype. Only 50 of these prototypes where ever made and this one, number 38, is headed to the Mecum Kansas City auction in April, 2014. Not only does this mean Boss have the honor of being one of only 50, it’s the first candy apple red Boss 429 ever built. This car was the 29th Mustang sold to the public in 1969.

The original Boss 302 was a road racing variant of Mustang designed to compete in Trans Am racing. By 1969, Chrysler had begun to dominate the NASCAR circuit. The Boss 429 was designed to compete wheel to wheel against Mopar’s 426 Hemi on the Ovals. Ford sub-contracted Dearborn, Michigan-based manufacturer Kar Kraft to build the Boss 429s. Since the Boss 302 bodies weren’t wide enough to house the 429 engines, Mach 1 bodies where used. The Ford 429 engine produced a claimed 375 Horsepower though many believe the horsepower ratings are closer to 500.

This particular Boss 429 has the 820-S NASCAR engine sitting in it’s bay. This was a 429 that has been tuned to compete in the NASCAR Grand National Division (now known as the Sprint Cup). The motor is tied a four speed ford transmission which sends the power to the rear wheels. The interior is made up of a wooden dash, leather seats and a big ol’ shifter on the floor.

The Mustang’s all American race inspired styling, combined with its herculean 429 motor and its legendary reputation means this car should fetch a pretty penny. Considering that it’s one of 50 we expect the car to win no less than 6 figures. How much do you think it will fetch at auction?