Well actually the old fuel cell was located where yours was. It is now the bilge and works very well for that purpose. I doubt very seriously ours holds 40 gallons, I could very well see 20 at most. Our fresh water tank is located just in front of the old fuel cell (our bilge).
Ours was transformed at one point, having a modern interior. Also, our chain plates are integrated into the hull with a cutter rig and twin backstays. It is very weird indeed how our boats are different. But they were not made for 'sail away' condition from my understanding. You bought the boat with the intention of customizing the interior and could be a sloop, cutter, or yawl sail plan.