SS-100-X was originally a standard 1961 Lincoln Continental four door convertible (model 74A) built by the Ford Motor Company and assembled at the Wixom, Michigan plant. It had a retail price of $7,347 (equivalent to $60,167, as of 2017).
The car was moved to the Experimental Garage at the Ford Proving Grounds where an additional 41 inches was added between the front and rear doors and just beyond the rear doors.navy blue color and taken to Hess & Eisenhardt of Cincinnati, Ohio, for reupholstering and further modifications to Secret Service specifications. During the refit the car had no bulletproof or bullet-resistant additions added. The windshield remained the standard two-ply safety glass which could be easily replaced at any dealership.
The car's frame was strengthened to accommodate the additional length and weight. It was painted a special
It was first delivered to the White House on June 15, 1961 and measured 255 inches (6.5 m) long, had a wheelbase of 156 inches (4.0 m), was 78.6 inches (2.00 m) wide, and 57 inches (1.4 m) high. It weighed 7,800 pounds (3,500 kg), up 1,585 pounds (719 kg) from factory weight, and was powered by a hand-built 350-horsepower 430-cubic-inch (7,000 cm3) Ford MEL engine.
An open car, the Lincoln was equipped with an assortment of tops, including a snap-together bubble top, a black cover for the bubble, a formal rear top and a stainless steel forward section (none of which were bulletproof). It also featured two-way radio telephones and retractable steps and grab-handles for Secret Service agents. No armor plate was added to the bodywork, but the undercarriage and all suspension components were strengthened. A hydraulically-lifted rear seat was fitted. At the time of the assassination, the Lincoln had been fitted with a 1962-model front clip (fenders, hood, grille and bumper assemblies).
It had a special short-turn radius, 61.9 feet (18.9 m), compared to 64 feet (20 m) on the 1950 Eisenhower "bubbletop" which had been its predecessor. Total cost of modifications was approximately $200,000 (equivalent to $1.26 million in 2016). The limousine was registered to the Ford Motor Company and was leased to the Secret Service for a nominal fee of $500 per year (equivalent to $4,095 in 2017).
The limousine carried the District of Columbia license plate GG 300. In November 2015, the license plates were sold at auction for $100,000.