Someone gave me a Paasche AB Turbo airbrush over the weekend. After looking at parts breakdowns and YouTube videos, I started taking it apart. However, I can't get the top & bottom shaft bearings (the screws under the top & bottom of the turbo cylinder) out or even loose. I'm afraid of stripping the screws by using too much force. Does anyone know of a technique, solvent or solution that would help loosen these?