Mark - have you ever researched thermal-dispersant coatings? "supposedly" when a part is painted with one, it actually sheds heat better than the bare aluminum. Might not be a huge difference, but maybe every little bit helps. The added benefit is that you could have a black frame and "motor". Would look nice with some color/graphic schemes.
TLTD Thermal Dispersant | Tech Line Coatings
TLTD Thermal Dispersant | Tech Line Coatings