Hi Chuck, while I totally agree painting is the way to go, if you are going to make cuts try looking at an Olfa Compass Cutter. It's the same concept as the Xacto in the compass, but a little sturdier and purpose-designed for cutting circles. I have used it many times to cut masks for hinomarus, and they come out nice and crisp every time. here is a link to someone that carries them (no affiliation):
http://www.adorama.com/ALVOLCMP1.html?gclid=CN-bzv_UucMCFWVp7AodsDQAug
Good luck with your project!
Paul
