Fair enough. I was experimenting with blue as the cold end of the scale. But the highlighted numbers (yellow or red) in addition to the gauge seem to be more effective at catching my eye. So all the new colors act like a green. Except "in the purple" just doesn't have the same ring as "in the green".
Also the only colors that show up on the CHT gauge are white (any color), yellow and red.
Hard to break away from the standard green, yellow and red. :-/