XML Fuel Tanks

I experimented with it and found that it IS possible. The only craft part that already has it is the Komodo Capsule.

@Toinkove, I'm aware of that. I meant if you could use XML to make a part ACTUALLY have 2 fuel tank components.

If you mean to hold different kinds of fuel types?
……
Really you can just as easily add two “tanks” together with different fuel types and they’ll look like the same tank!