Thanks guys.
I didn’t realize there was silver paint and clear coat on most of the motor.
Some scrubbing pads and an orbital cleaning/buffing wheel seem in order where it can work. Tape a scrubbing pad on a spatula to get in between the fins.
Philly - a nicely oiled gas tank is one thing, but oil on the motor doesn’t seem like a good idea.
There are airplane and boat cleaning products out there for aluminum, but not sure how well they work on heavier oxidation.
Here some stuff at O’Reilly that might be better than nothing and price doesn’t break the bank. This stuff seems more like a last step.
https://www.oreillyauto.com/detail/c/superior-products/superior-products-1-ga...I do have a respiratory mask and googles when needed.