In general, I think it is not good to use the location of the mintmark to determine type. Mintmark for these coins were hand stamped onto the dies and the exact location could differ die to die. The 2 coins in your graphic certainly indicates a difference in the date relative to the mintmark but I'm not sure that carries over to all 1970S large date/small date coins. I think it's better to look at the position of the 7 and the shape of the 9 as Essor Prof discusses in this post: https://en.numista.com/forum/topic109180.html