Aging a Finish
If you are trying to artificially age a finish there are a few things to understand. The law of colours is a real thing. Using a tinted (amber) lacquer over a colour will change the colour of your colour coat. It can be done with amazing results. Example, blue will become green, anything red will become orange, etc. If you apply your aged clear at the very end you will just sand through it in the buffing and polishing step. Sometimes adding a few clear coats after your colour coat will lessen the colour change when using a tinted clear. Experiment a bit and find what works for you. Fender and Gibson have made millions by doing this to replicate old finishes.