if you are not going the chemical route, you can paint the tracks to good effect. Clean them up. Then give a base coat of primer red. Once dry, mix a batch of Tamiya Hull Red, Black and Aluminum. About 80, 10, 10. Spray this on in light coats, about 2-3 passes. Then weather them out the way you wish. Pastels, pigments, mud, dry brush, etc.