color mapping

Trying to change a couple of colors using Preflight.

Created a Profile with a Fixup and successfully changed my green from RGB 26,133,66 to RGB 16,106,25

Created another fixup to darken a gray from RGB 217 216 216 to RGB 116 116 117, but it does not work. 

Why?

These colors were taken from the Edit Tool itself -- so they should be accurate, right?  And everything worked for the green but does not work for the gray.

What am I doing wrong?   Do I need to run another conversion first for the gray?  If so, which one?