It's always hard to get a colour 100% right. Even then, it will look different to all the different users because of colour temperature settings in their monitors, the monitor type, etc etc.

What i usually do, and that usually yields good results, is to use Photoshop's colour picking tool and pick the colours from an actual aircraft picture. Even then, depending on the light conditions, the colour might not be accurate  ::)

It's looking real nice, and i can't wait to fly it  ;)