Good Morning! I have this part (shown below) that calls out a slot as the tertiary datum and I am having trouble trying to get the true position to show the MMC to .0002 for the callout for -D-. I am measuring it by taking 1 hit on each side of the slot and making a midpoint between the two. I am also not able to add the MMC modifier to either of the .100 TP or Perpendicular callout or the .125 TP callout. Is there a certain way to do this?