Mini Hydro Boat Design Question

[lakshmi369]

So.... I just got an older Mini Hydro to fix up. The design is somewhat of a mystery to me and I know some people out there will be right on this. I tried including a picture but it wont load. This design that has a hole right through the back of the hull where the motor goes and sticks out the bottom of the boat. I am looking for info on how the motor might have been mounted in this case as I may be fabricating a bit more that I planned....sadly! Other question....has anyone circumvented this problem by fiberglassing over the hole and making an actual transom for the motor?