Hey, Im an aircraft maintenance engineer in Canada, the company I work for maintains four Kingair 350s for BC ambulance.
The forward exhausting engines are a nightmare for paint, the inboard wing on the left side, and outboard wing on the right side will be an absolute nightmare.
Aircraft paint will not gloss up like car paint will, it's usually a very hard single stage, though our wing lockers and nacelles are a red base/clear.
I use Meg's M83 (by the gallon) and Rejex with a rotary air polisher.
M83 on Wool
M83 on Yellow Foam
Rejex on Tan Foam
It's a frustrating job, youre more just deep-cleaning the paint rather than polishing it. The stupid engine design will have it all stained and disgusting next time it gets flown anyways.
If you have any more questions feel free to ask!
This is C-FRLD, our priority plane in Kelowna, and one that I'm polishing almost every night in an attempt to keep clean.
Notice the staining on the right wing just ourboard of the engine nacelle? Thats what youll be battleing.