Richard,
The Aqua-ute was build we think by a man called LeBrugen?? He only made a few and we had one as well as another local called Bert. Bert is still alive and would know more if you were interested. My father gave his about 20 years ago to Bert who had sold his many years earlier. It was a trailer, boat and caravan. In the photos you will see that it had a front fin that was also the tow bar. An anchor sat on this tow bar and was used when boating. You could leave the wheels on for short trips but were removed by a pin while in the water. It had a windscreen that folded down, seats on either side and the bottom floor could be lifted up to make a flat platform that was level with the seats. In one of the photos you can see the top of the wheel arch. It was incredibly stable as it had such a wide bottom. We had around a nine horsepower motor on it and it when at a reasonable speed.
Regards David