70 CUDA Chrome front bumper

Looking for some help, What is it that makes a 70 CUDA CHROME front bumper a 1 year only? Was 70 CUDA front bumper one year only because of the jack hook cut out vs 71? ( small cut out in 70 vs much longer cut out for 71 ) Or are there other differences? I am aware of the later bumper differences, also What is the easiest way to tell a repop vs OE if there is one? Thank you for your input.
Author: sxpckcuda