Fender Tag
A lot will depend on which year and plant. I know there was one plant that mounted the fender tag with rivets and used a different code for options. The other plants used phillips head screws. Most years used rivets for the VIN but not all. '69 and newer cars had the VIN match the radiator support stamping and sometime a trunk stamping. '70 and newer had a door sticker with the VIN too. '68 and older had a shipping order number on the fender tag which matched the radiator support.