Are you talking shading as in tones? Blue/grey? Or as in shadows (darker spots around the glare, usually greys)?
Here's a closeup of the long-awaited rabbit nose art, and a slightly-reduced-glare screen shot. One problem with the left wing/right wing was that the sun was toward the left, and so it looks like the right is less shiny, but the in-game glare was there at different angles.
Rabbit:

I'm getting closer. I actually kind of like the way it's looking now. Most of the process I was like "okay... okay... okay" but then when I started tweaking this last setup I was thinking "Okay!! Now THAT looks good!" so I'm happy about my progress. I don't know what it was, but something just "clicked" with this last attempt.

EDIT: While I'm fine-tuning the metal (I think I'm close to done) this would be a good time for any nit-picks and the like, any errors in markings, size, wrong angle in relationship to mars and venus, the planets aren't aligned for the type of anti-glare I used, and so forth.