To avoid the exceptionally high development and production costs of its largely hand-built, extremely low-volume predecessor, the Mark III shared its chassis with the four door Ford Thunderbird.

Model-specific design elements, including its hidden headlamps and large chrome grille distinguished the two — while sharing the same roof structure and rear windows, retractable into the C pillar, of the two door Thunderbird.

[2] Ford manufactured the Mark III at its Wixom Assembly Plant facility in Michigan alongside the Thunderbird and the Lincoln Continental.

The Continental Mark III was the brainchild of Lee Iacocca, Ford's vice-president, car and truck group in 1965, who directed Design Vice President, Gene Bordinat, to "put a Rolls-Royce grille on a Thunderbird"[3] that September.

With the Thunderbird "dying in the marketplace"[3] Iacocca wanted to put the company's development investment to better use by expanding its platform over several models.

[4] The Mark III was intended to compete head-to-head with the top of the domestic personal luxury car market, Cadillac's then rear wheel drive seventh generation Eldorado.

This placed it above the second-tier premium personal luxury cars such as the Ford Thunderbird, Buick Riviera, Oldsmobile Toronado and Chrysler New Yorker coupe.

Iacocca said, "We brought out the Mark III in April 1968, and in its very first year it outsold the Cadillac Eldorado, which had been our long-range goal.

"[5] Iacocca explained that this transformed the Lincoln-Mercury Division from losing money on every luxury car (via low unit sales on high fixed costs) to a profit center, making the new Mark series as big a success as any he ever had in his career[6]—a remarkable statement from an executive who led the programs for the original Ford Mustang and the Chrysler minivan family.

One reason for the rarity of the plain-roofed version is the fact that the roof was made in two pieces and required extra preparation at the factory to conceal the seam; consequently, its availability was not widely advertised.

Although horsepower remained unchanged at 365, Federal emissions requirements were met by the installation of "Thermactor" air injection pumps on the 460 CID engine.

Little changed from the 1970 model; tinted glass became standard, as did automatic climate-controlled air conditioning and Sure-Trak anti-lock brakes.

Horsepower remained unchanged at 365, but the 460 CID V8 engine gained a more sophisticated thermostatic air cleaner assembly with its associated ductwork.

In its second annual King of the Hill contest, Motor Trend (July, 1971) again gave the Continental Mark III the nod by a wider margin than 1970 despite it being basically a warmed-over 1968 model while the Cadillac was all-new from the ground up.

M/T noted that the Mark III's leather interior was far more luxurious and better detailed than the test Eldorado's nylon cloth and the Continental's real wood dash trim was far more attractive than the Cadillac's simulate.

Golfers Arnold Palmer and Byron Nelson also served as brand ambassadors for the vehicle In cinema One of the most notable movie appearances of the Continental Mark III is the 1977 horror film The Car which featured a highly customized 1971 Lincoln Continental Mark III designed by famed Hollywood car customizer George Barris.