Chevrolet had been in existence 46 years when the legendary Impala was majestically assembled for the first time back in 1957 for the 1958 model year. The Impala, named after the medium-sized African antelopes, was originally introduced as a top-of-the-line Chevy Bel Air, a car that had been in rotation since the 1950 model year. The Bel …