A '67 400 car that started life as a 6 cyl car. VIN tag on the jamb and the cowl tag matched each other and the PHS, but the cowl VIN did not.

When filled, you can view these with the cowl grille off using a mirror and flashlight from below the cowl.

The engine date codes were later than the build date too, which even if the tags were right would have overruled the "numbers matching" claim.