We want to perform the next steps before the clay dries up. First, we want to take out a small chunk of the clay at the back, and drill a hole at an angle. There, we'll feed the sleeve and drive shaft through and install the propeller. Do not ever glue a sleeve into place. It needs to remain flexible. Instead, we use a liberal amount of silicone to hold it in place, and seal the hole inside and out of the body (as shown in the following image):

Now, it's time to make our motor mount. We wanted to see exactly where the drive shaft will be, the angle it's at, and where the hookup to the motor is. We do the same thing we did for the drive-shaft sleeve on the front of the boat. There, we put the long end of the water-cooling tube. We do this before placing the motor mount, because otherwise we wouldn't be able to get at it. This tube will take in water for the water cooling (as shown in the following image). After waiting for the silicone to dry, we can trim it...