The Boss Mustang is among the most easily identifiable and coveted muscle car collectibles on the planet, all the more so because Ford brought the Boss back for a brief two-year run for the 2012 and 2013 model years. This has caused a resurgence in interest among collectors and restoration experts, especially the more creative types who pursue “What if?” cars that add a unique twist to any collection.

This 1970 Ford Mustang Boss 351 convertible, up for grabs on the Hemmings Classified section, is one such “What if?” car that was never actually made, but represents what could-have-been had Ford decided a droptop Boss was what buyers wanted.

Ford never actually built a Boss convertible Mustang, and the Boss 351 engine under the hood of this custom creation was not even an option in 1970. But thanks to a lot of reinforcing of the under body, this Mustang is one stiff customer, able to easily handle the extra output of the Boss V8 engine. This includes a one-piece seat frame and a steel plate underneath the seats to make the ride “extra tight” in the words of the seller.

The Boss 351 Cleveland engine is mildly ported with 2-barrel Cleveland heads and a valvetrain borrowed from an actual Boss 351. A Hurst four-speed shifter allows drivers to row through the gears themselves, and out back the 9-inch rear end has 3:91 gears. In other words, this unique Mustang can certainly get going should the horsepower be called upon.

It’s a unique ride to be sure, and for the asking price of $46,900, it’s also about half the cost of a real Boss Mustang, but without the “garage queen” stigma. Would you add this Boss droptop to your collection, or just drive it like you stole it?