The story
During the 1990s, Mastretta focused on microbus (Mexico City metropolitan minibuses) body chassis design and engineering, as well as that of urban buses. This experience led to the construction of their first kit-car in 1995, the Unediseño-Mastretta MXA. The Unediseño Mastretta was built on the chassis of the Volkswagen Beetle, called the "Vocho" in Mexico, and used the Volkswagen air-cooled engine as power source. For this prototype, the engine delivered 44 bhp (33 kW; 45 PS) and reached a top speed of 127 km/h (79 mph).
A few hand-made units were exported to Germany, Japan and the USA, where the kit-car marketing was attractive for many collectors at the time; those that remain in Mexico are owned by Mastretta. A variation of the same model, the MXB, was also built. It featured different headlights and other minor modifications.
Automóvil Panamericano car magazine's February 1998 annual edition of Modelos (Models, a special catalogue with information about every commercial model on Earth and since that year, a few pages dedicated to kit-car makers) featured a paragraph on the Unediseño Mastretta.
From Wikipedia’s article on Mastretta, shared under CC BY-SA 4.0.4