An inboard is a lot easier to make then a pod drive. For an inboard you go to an ev store like cloudelectric or to your local forklift store and buy...
Differential expansion is the main reason, it's done by using a double layer of foil. Pouring the slab and strip foundations or frost walls in one go...
He uses this arrangement of peak halyard. You can clearly see it in the video when he talks leaning on the gaff (minute 11), the grey dyneema bridle...