the dream of my youth was the “Egli turbo mrd 1”.
Maybe that is some inspiration ?
I love to see the NOS bottle.
Don’t hide it behind a fairing 😉
From a visual point of view, the center of gravity, easy access and with good chance to have a solid fixing option, I love to see the bootle left hand side mounted at that frame tube coming from swing arm bearing going to upper shock absorber mounting stud.
Gives the bottle approx. 30° lean to the back.
If available, I would prepare another fuel tank. Also an LTD/CSR fuel tank will fit the B-frame with really minor changes (just the central “pin” in the bottom rear and it’s counterpart in the frame).