Iv taken to using my carburetor dip, takes it right off after a 30 minute soak. Maybe spray carb cleaner would work just as good. Iv used acetone in the past and while not that fast it does work after going over it a couple of times. Iv heard you can burn it off, but you would need to move fast and some what know what you are doing with the heat unless you want it heat colored too. Always remove any plastic insulators of course.
I had a mod once that had so much clear coat on it it would`nt fire, it was totally foaling the conductivity within the threads. SMH.