Here are the 4 Topps 1960 cards I mentioned in post 985. In each case the gray back is on top and white back on bottom
--On Grunwald 427, there is dot to right of his cap in insert on white back
--On Rodgers, 431, the white mark just above the logo in lower left is bigger in gray back version
--On Jones, 410, there is minor white area above the logo on gray back and a red area in the ball within the logo on white back
--On Williams, 414, there is a line/mark at end of his truncated arm in insert on gray back. Looks blueish to me in hand
I have not looked at the backs of all the cards in the series to see if there are differences beyond the stock differences. And would not be surprised if I missed other front differences