I've seen these designs floating around and I wonder where they are going to put the fuel. From a 737 MAX diagram and tank sizes, the wing tanks are nearly 1/3

I've seen these designs floating around and I wonder where they are going to put the fuel. From a 737 MAX diagram and tank sizes, the wing tanks are nearly 1/3 of the fuel and the center tank is partially in the wings. I'd estimate well over half the fuel is spaces of the wing structure.