No kidding, what about the early jet skis? They were a floating motor with a gas tank! I know it looks crazy and stupid, but the tank is outside of the boat. Just look at all of the older outboard jon boats, whalers, etc. All of them had exterior portable tanks, usually metal. I would also argue that the old metal tanks are of a significant thinner gague metal than this one....I just hope it is baffled and secure.