I must give the credit for this idea to some unknown fisherman from the Cook Islands . No doubt similar solutions are used on many Pacific islands. On one of my visits there, I saw a small flat bottomed plywood canoe with an outboard bracket that consisted of a length of 2x4 shoved through two rectangular holes in the sides of the canoe. Nothing could be simpler or less prone to failure than this.
The above drawing shows the structure used on the Va'a Motu design. The wood piece lashed on top of the gunwales allows more distance between the gudgeons for better rudder stability.
If the canoe is heavily loaded or trimmed down at the stern, the waves can hit the mount. A thin plywood shield, held on with webbing hinges and a lashing, deflects any spray away from the motor.
On the Va'a Motu I used a fabric spray shield attached with snap fasteners on the outboard motor side.
The Va'a Motu cassette rudder on its mount.