There are three areas I first look at on ALL 1972's (P,D,S)and that is the upper left corner od D for notch, The N for the raised inside portion of the left upright, and the upper left tip of the you for NW doubling. There are many other points to determine MDD, but I find these to be the easiest for me.



















on the real doubled dies, you could check this web site and see what the real hub doubling will look like:






