Very cool truck! My experience is GM used red oxide primer at the factory, not grey. As with anything there could be exceptions. The way to tell is to look at chips that go all the way to metal. You'll be able to see the layers of paint. If there's nothing between the grey (looks more like blue on my monitor) and the metal it's likely the base primer. If there's another color between it and the body, the truck has had a repaint. Either way you and your wife have a real treasure and a valuable piece of history. I'm an original kind of guy so my recommendation is to preserve it, not hot rod it. It's only original once.
Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.
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