"Other different characteristics" The key to the time period as to when a 'cuda crumple hood was issued would be to find a 1970 hood with the zones in it. By that I mean, one that does not have the three cast-from-the-factory holes in the top side of the hood and the same in the bottom side of the hood(there, there are three circles larger than the ones on the top of the hood). The only hood close to this that I have seen was one on an all original car at Spring Fling years ago. It was a 1970 hood on a very early production 1971 six bbl car. The underside of the hood did not have the three larger circles(indicating a 1970 hood), but the pins from the PLYMOUTH nameplate had been crudely drilled through the hood. The two pictures that Mike posted of the "with and without" zones do not show the very top of the hood in either case.