Hi The bird,
It is also not very clear if this fuel can be used i.c.o. gravity feeding.
Gravity feeding simply needs the fuel to run "downhill" to the engine. The engines hang below the wing, so gravity feeding is possible from the wing tanks.
The fuel level in the centre tank will mostly be below the engines and below the fuel inlet from the wing tank, therefore gravity feeding is impossible.
Have you ever tried to syphon water from an aquarium or fuel from a tank?