If the Ford Mustang is a pony car, this must be a Clydesdale. Specialty vehicle builder and accessory sales outlet Michigan Vehicle Solutions has a surprise hit on its hands with a fastback-style ...

Mustang Fastback-inspired bed cap for Ford F-150, via Michigan Vehicle Solutions The Aero X, as the company calls it, costs $3,995 and works with 2015 and newer F-150 models with 5.5- and 6.5-foot ...

The Michigan company will sell the Aero X bed cap for $3,995, but at the time of writing, it was only available for 2015 Ford F-150 models with the 5.5-foot and 6.5-foot beds.

That fastback Ford F-150 conversion that's been making the rounds has generated a lot of interest online—more than 400 inquiries, according to the company.