The set screw is frozen badly, and awkward to work on in the small recessed space. Any tips on freeing it? Besides heating it up...! Or has anyone got another way to chip away the year's creosote behind the wheel without risking damaging a vane? (Yes, there's some creosote from burning super-hot softwood pellets, so sue me.) Harman's official cleaning tool is "ok" for this but hard to control with enough strength to clean the back wall without endangering the fragile vanes you are sticking it between to do that. This baby is like 10 years old now and still great.