RE: Nitroplanes 90" P-38 (1/7 scale) with 3 piece wing and more
Gary are the retracts air up/ spring down?
Easiest set up for closing the gear door is a piece of clear fishing line. One end on the outer end of the door, other to the inside of the pocket. As gear closes it contacts the line and shuts the door behind it. As gear extends it releases tension on the line, door drops open and gear extends. Pretty much fail safe.
I always worry about having a gear door set up that fails and makes you land wheels up.