It had a long and painful gestation, too. Engineering for the retractable roof dates back to the late 1940s, and a 1953 proposal for the Lincoln Continental Mark II’s hardtop–one of two competing retractable roof systems within Ford Motor Company. The Mark II’s roof was extremely expensive, both to design and build, and never made it to production. To amortize the cost, it was reused in the 1957 Skyliner, abandoning an original Gil Spear roof-on-rails proposal which didn’t meet Henry Ford II’s mandate that the roof should be able to be folded inside a seven-foot-tall garage. While far more complicated, Ford would milk the Mark II design for the next decade in attempt to make it profitable: After the Skyliner, it turned up again in the 1960 Thunderbird, then back with Lincoln again starting with the 1961 Continental.

The design of the 1966-’67 Continentals inherited interior features from a 1964 redesign, with a controversial new dash and notably different exterior for 1966. A 126-inch wheelbase was unchanged, but overall length increased by five inches, to 220.9, and the car was wider, as well. These were the purest of the slab-sided Lincolns, with an almost perfectly flat expanse from front to rear, highlighted by a secondary waterfall curve and Lincoln’s classic bracket-style bumpers. Front and rear profiles were nearly perfect reflections of each other, but inverted to carry the Lincoln side step up to the rear.

Lincoln also got its first all new engine since 1958, a tremendous 462-cu.in. V-8 good for 340hp and 485-lbs.ft. of torque. Cadillac had to make do with the second largest production engine, a 320hp 429. With the introduction of a popular two-door coupe, Lincoln saw its best year in history, selling 54,755 cars.

The Continental convertible, however, had little to do with that success. Over the entire 1961-’67 production run, a total of 21,337 were built and in its best year, 1965, it sold only 3,356 units. In 1967, that was 2,276 cars and that despite prices lowered from $6,713 in 1961 to $6,449.

By 1967 the Continental convertible was a virtually forgotten car–no eulogies were written, yet Lincoln never again made a convertible after 1967, making it one of the most distinctive and rarest cars of the era.