If you want exact color matching, there is only one way to do it, Duracoat, Ceracoat, or what have you, the entire thing at the same time. Different aluminum will take different shades of anodizing even if done at the same time, and if you coat with mixes using different batches, even they might not match exactly. Trying to get different parts from different makers to match is darned near impossible. Or to make it simple, don’t worry about it. If your OCD is that bad,seek professional help.😉