Help Redesign Q - Fuel Tank Location - Stringers on Modern Mid Cabins

I have a question I hope someone can help me with. Where are the fuel tanks located on these modern mid cabin express boats like the new Rinker 35 / 39 and Formula. How do they have a reduced stringer system? Were the boats of the 80's and 90's overkill with regard to stringers? Or is it a function of strength through coring

The Boats of the 1980's an 90's had big longitudinal stringers all over the place. Now you have boats with mid cabins that go way back yet they carry 235 - 300 gallons of fuel yet barely a stringer is in sight. 250 gallons takes up a lot of room

I can't seem to find any pictures from today's manufacturers/boats of the hull with just the tanks and stringers.

Can anybody help

I have a 1986 42 footer "all apart" with new transom, stringers and bulkheads going in. If there was ever a time for mods this would be it. I have a 235 gallon central belly tank under the cockpit sole with corresponding 24" stringers holding it in place. Outboard of this is an 8" stringer and an 18" stringer another 12" outboard. All in all it is a massive underutilization of space.

Does anybody have any ideas

 

Generally these tanks are forward of the engine space as low as possible. Usually buried in the bilge. Occasionally you will find one with twin tanks mounted outboard on either side but this is the exception. I'm not saying the bilge is a good location. Putting the tank in the bilge exposes it to water and corrosion problems, but it does lower the center of gravity and gets the tank below the engine fuel inlet so they don't have to use an anit-siphon valve.