After the first testdrive I noticed that the chosen version of the propulsion couldn't adjust to the right belt tension without the belt jumping tooths over the gears. The axle of the motor is only fixed in one bearing so I placed a second bearing in the gearbox to fix the motor axle.
After making the drawings in my CAD program it looks promising and I started to get the material and start milling.
The eight plates for the four gearboxes
The first backplate
Making of the cool holes for the brushless motor
Making the hole for the brushless motor with the boring head.
The cool holes open
The cool and mounting holes in the motorplate
Milling the adjust blocks.
Making the hole for the bearing
The gearbox assy assembled
The gearboxes mounted in the hull.