From some other mopar enthusiast that I have talked to: After tax day in 1970 (April 15) e-body (not sure about b-body)cars were suppose to be equiped with crumple zones. Story goes that a driver was decapitated because the hoods didn't crumple under impact, thus crumple zones were mandated. I believe their are two types of Shaker cuda hoods. Crumple zone or non-crumple zone hoods. Their should be 2 crumple zones on bottom side towards the front outer edges of the hood. Challengers I believe have 3 different types of shaker hoods depending on SPD.

Im just wondering if some hoods might have accidently got put on some cars without the crumple zones in 1971

If anyone knows anything about shaker hoods that im not stating or if I am wrong please feel free to correct me!!!