Here is the key to the design of the pod covering the rear landing gears – it is airfoil shaped. This is not immediately obvious when looking at the formers, but they (almost obviously) are airfoil shaped.
It can be seen on the pictures of the actual aircraft.
I will implement these pods as two fibre-glass shells and a simple plywood skeleton. This is a strong and light building-method with room inside for the landing gears.