Customizing AOE Leader Class Optimus Prime Truck Window?

I've seen many reviews of Hasbro's retail release of the Age of Extinction Generations Leader Class Optimus Prime, and all of them had a complaint of the truck window and sword getting a golden shower of yellow. I myself don't like it, so when I get my hands on the Leader Prime I'm going to modify the window. But just one thing... how should I paint the window? Any ideas?