I posted the window sticker in the photos .. I think you can tell a lot by that. the door sticker is dated 10/70 . I don't know how to tell . maybe somebody will post it if they can tell by that data ? I have always been told that this car is the only 1971 gy8-shaker six pack car made ? I have seen other shaker gy8 cars but , none are six packs.....