I have two differnet front bumper both have the jack cut out on the bottom not vertical slot so I think they are 1970 and 1971. on the top at the bend on the end were the v shape is on one it is smooth curve and on the other it looks machined and has square notches cut into it I think the notches are for black rubber inserts that I have seen on some challenger bumpers.

I need to find out which is correct for 1970 challenger

this is the part of the bumper that wraps around the fender and the v shape is when you look down from the top

Ok< I just looked at the front bumper off my unmolested 70 Challenger Convertible I got from the original owner and it has just the V without the squared notches. I have what I remember to the best of my knowledge a 71 front bumper on my 74 Challenger and it has the squared notches. I believe that the squared notches would be correct for the 71-72 as I have a friend with a 72 and it has the rubber fillers like a 70-72 would. Hope this info helps. Greg

I think I have the original from my Dec 69 LA built 1970 challenger in the shed, I'll snap a pic of it tomorrow

Thank you both for the help so far it sounds like the one with the notches is for 71 and the smooth v shape is 70. these bumper do not have the vertical slot for the jack which is think is for 72 an 73 but I am not sure.