Ford Motor Company launched the Mercury brand in 1939 as an attempt to offer its customers a car that was more upscale than its standard Ford models but not as expensive as Lincoln. They were mimicking General Motors and its long-established its hierarchy of brands that we've discussed before. Ford saw Mercury as its answer to Oldsmobile or Buick. (Later they tried to split the difference too finely with Edsel, but with four model series in two basic bodies it was unclear whether Edsel was intended to be between Ford and Mercury, between Mercury and Lincoln, or both, and the market rejected it.)
In the late 1950s Mercury was allowed to build cars on a longer wheelbase with body styling that was completely different from contemporary Fords, with no shared exterior panels. This lasted for about a decade, until cost-cutting started becoming a larger concern to auto makers, and it was probably Mercury's most successful period. (Note that this is just my opinion and I'm not backing it up with any hard data.)
With the enormous success of the Mustang (talk about tapping into the zeitgeist), Mercury understandably wanted a piece of the action. For 1967, when the Mustang received its first restyling since its introduction in the spring of 1964, they got their counterpart: the original Cougar. The Cougar shared the Mustang's basic chassis structure, but rode on a wheelbase that was three inches longer and had more sound insulation, resulting in a more refined yet still sporty package.
According to other videos on YouTube, some people think these lights activate too slowly and replace them with LED units, but I can't see doing that to one of these. All Cougars came standard with a 289 cubic-inch V8, bucket seats (would anyone have wanted a bench seat?), and a floor-mounted three-speed stick shift.
The 1968 models were virtually identical except for different badges and the addition of federally-mandated side marker lights. The redesign for 1969 followed the Mustang's, getting larger and heavier, and while the 1969-70 Cougar is still an attractive car, it feels less special than the first version.
Unlike the Mustang, the 1967-68 Cougar was available only as a two-door hardtop; a convertible was added for 1969. I have always thought that the first Cougar would have looked great as a convertible, and figured someone out there would have had the same thought along with the means to make it happen. But given the amount of work involved, I'd settle for a hardtop.
Coincidentally, over the weekend as I was thinking about writing this piece, the Autos section of the New York Times ran an article about Kevin Marti, who offers documentation services on Ford Motor Company products. His first car was a '67 Cougar, and he did to the car just what I hoped someone would do: cut off the roof. Of course, it isn't that easy to turn a car into a convertible (and if you follow the link and read that article, you'll get more details), but eventually Marti was able to get his Cougar properly squared away using parts salvaged from Mustang convertibles:
Old Car Brochures (top); The New York Times (bottom).