Fuel tank replacement

[1998 Century 2300]

After my second day of boating on my recently purchased Century 2300 CC I step on my boat to discover a bilge full of gas. After coming to the conclusion that there is a leak in the bottom of my 99 gal. aluminum tank, I realized that there is no hatch in my deck to remove the tank. I am not going to do the fiberglass repair but I was hoping I could save myself some money on the repair by getting the layout of the hull/stringers. That way I could cut the deck, remove the tank, install the new tank, and then bring the boat to a fiberglass repair guy for him to finish the deck. Does anyone have a detail of the hull or any other smart advice?