and "to use even the harder to burn heavy gasoline molecules" – thus, claiming mileage increases of 40 to 57%. However, the EPA tests did not fully support the performance and economy claims that were to be achieved by these modifications in comparison to standard factory tuned vehicles. Concept cars The AMC Hornet platform served as the basis for evaluating design and styling ideas by AMC. In the late-2000s, the Hornet name was revived for a Dodge concept car. Cowboy Although both predecessor companies (Nash and Hudson) had built work trucks, the merged successor (American Motors Corporation) never developed and marketed a truck line until it purchased Jeep. In the early 1970s, AMC was planning a compact coupé utility (pickup) based on the Hornet to compete with the increasing sales of Japanese compact pickup models. Work began by having the Jeep styling studio convert a Hornet into a pickup with three objectives: to compete in size with the imported trucks, rival the Chevrolet El Camino in appearance, and have a lower cost than both of them. A further goal was to achieve the most return from AMC's $40 million investment in engineering and production dies needed to bring the sleek Hornet compact to market. Prototypes called the Cowboy were developed under the leadership of Jim Alexander. The first proposal had an El Camino design with a "sweeping panel from the rear of the cab, flowing into and becoming the side of the truck bed." This would have been expensive to develop so Alexander, an AMC product planner, proposed a separate cargo bed mounted on a stub frame serving for the rear half of the unibody vehicle with a gas tank from an Ambassador welded under the front half of the cargo bed and the spare tire fitting under the back half. Documentation from the development process indicates three prototypes with a Hornet-based cab, Jeep-style grille treatments, and a Gremlin version. The design called for a cargo box and the first prototype used doors from a four-door Hornet. This short design did not work well and the cab was opened up by incorporating units from a two-door sedan along with a new upper window frame and a "K-pillar effect" that improved the design and for better sight lines. One red prototype vehicle featured a modified AMC Gremlin front design and a cargo box with a Jeep logo on the tailgate, but