The landing Gear is adjustable - held together with magnets it can be positioned either DOWN ...
The sole of the landing gear footfits the recess in the outer skin when retracted so it doesn't need a cover and is held up by a couple of small magnets in the top of the foot. When the Landing gear is down, a couple of steel pins are inserted on the foot and attach to the hull, again with magnets.
As well as laser cut components I am going to have the landing gear 3D printed. The tubes and steel pins are simple modelling accessories. So, this is still looking like it might be sellable - but it wont be cheap.