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1978 was significant because it marked the cars 25th anniversary of production. Recognizing the achievement of manufacturing a car for a quarter-century, Chevrolet commemorated this accomplishment by introducing two special-edition Corvette that year.  The first of these was known as the "Silver Anniversary" edition Corvette.  It featured a two-tone silver over gray exterior with special pin-striping and special "25th Anniversary" badging.
The 1978 Silver Anniversary Edition Corvette was developed to offer consumers a “collectible” model that commemorated one of Corvette’s milestone production anniversaries (its twenty-fifth anniversary in this case) in a way that had ever been done previously with any Corvette model year that had come before it. The car was mechanically identical to 1978 counterparts.
While the redesign gave the Corvette a fresh look for the new model year, Chevrolet also recognized the importance of commemorating the car's quarter-century of production.  For the first time in the brand's history, two special-edition Corvettes were introduced for the 1978 model year: the Silver Anniversary Edition and the Indy Pace Car coupes. On March 15, 1977, the 500,000th Corvette rolled off the assembly line at Chevrolet's St. Louis manufacturing plant.