The pair of "1968" Lincoln Continental "follow-up cars" delivered to the Secret Service for use as "security vehicles in official parades" began life as 1967 4-door convertibles. Special features of each car, which had been updated with 1968 exterior cosmetics, included 11-inch wide runing boards with assist bars and handles, an 11-inch retractable platform and assist bars across the back, rear doors that fold to allow the agents to enter from the running boards while the car is moving, a transparent vinyl convertible top, rear-facing center front seat, "highly advanced" electronic communications systems, public address speakers, siren and red flasher lights. Interestingly, the 1967 model interiors were retained in these Lehmann-Peterson conversions.

From the rear three-quarter, the White House Lincoln Continental security vehicles looked like this. Notice that the bumper served as both the backbone and cosmetic cover for the retractable rear platform used by Secret Service agents. Also visible is the deck lid-mounted assist rail that could, likewise, be hydraulically retracted. A story making the rounds at Ford Engineering when these cars were placed into service, was that the agents, who had been accustomed to tramping heavily on the accelerator pedals of their huge commerical-chassised 1956 Cadillac predecessors, were more than a bit startled by the snappy response. At least one "real" 1968 Lincoln Continental convertible was built, a Daulton (light) Blue prototype last seen at Ford's Michigan Proving Ground during the summer of 1967.