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Are you talking about the actual,
metal trim tag that is attached to the
body at the front of the door jam, or the blue paper tag on rear edge of the door itself?
If the metal trim tag is gone, it's going to be harder to determine the original color without the build sheet/tank sticker, but maybe not impossible.
Pull the carpet back from the sill plates, and look under there for evidence. These cars were originally painted with no trim/interior stuff, so the floors would have substantial overspray of the color. Most repaints do not go through the trouble of removing the interior and covering all of the original color. Also, the hood hinges may still have some of the original color on them, as they were on the car when it was painted.
You might take some of the interior trim pieces off, and see if there is a different color under them than what is on the car.
As far as interior color, it's next to impossible to determine what it had originally without the trim tag, or build sheet, as the interior can be completely changed, with no evidence of the change in either color, or fabrics.
Do you think the car has had a color change, or are you just wanting to determine if the colors it has are original?
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Joel Adams
C3VR Lifetime Member #56
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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"