I'm not questioning anybodies answer on this subject. 69houdini's reply might be most accurate. I just finished (well almost) restoring my 11A LOS built 67 Coupe. It had what really appeared to be original GM Decals on the backs of both Doors. The Decals were somewhat faded, and the backs of the doors had never been painted. The complete rest of the car appeared mostly original (unrestored). I'm just sayin', 69houdini's explanation might be the most accurate. For me, they were there, so they're going back on.