Hello,
There's some good stuff on here on marking quens, but if you don't get a marking pen can you just use acrylic paint or such? I heard fingernail polish is toxic. Thanks.
I use to use Testors model paint. The have a paint pen that works well. I have also heard of people using whiteout and then numbering. Just keep in mind, you want something that isn't going to wear off too easy.