With the talented builders out there, it is pretty risky business certifying any car these days. You would pretty well have to strip a car to bare metal to have any idea what has been modified and changed. GM of Canada just tells you what options came from the factory with a given VIN. They don't put themselves in the position of verifying the authenticity of a given car. That can be foolhardy from a legal standpoint. Right about now certifications are going to get very thorough and very costly if you can find anyone to do it at all.
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Chevelleless after 46 years......but we did find a low mileage, six speed, silver 2005 Corvette. It will just have to do for now.