Chevrolet never built this car - Joel Rosen did, working out of his shop on Sunrise Highway in Baldwin, New York, where he took brand new Corvettes from Baldwin Chevrolet and tore them apart before they ever reached a customer's driveway.  His "Phase III GT" treatment included a reworked big-block - tuned well past anything GM offered from the factory, paired with a completely different rear window that replaced the production backlight with a fastback style panel, plus fender flares, a custom hood, and side exhaust. Buyers got a real warranty and financing through the dealership, which is what separated Baldwin-Motion from a simple aftermarket build.  The cars left the showroom with a Chevrolet title and invoice, but almost nothing about its bodywork or its engine matched what left the St. Louis factory. Rosen built only a handful of Phase III GT Corvettes total. Whether that makes each one more of a Corvette or less of one depends entirely on what you think the name is supposed to guarantee.
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