I agree the Rossi is REAL happy swinging a 9x8 APC, I am sure you could use a 10x7 or 9x9 but the 9x8 just seems like the sweet-spot for the Italion Stallion! The mini-tuned pipe seems to be the best of both worlds, though I have not run the Pitts style muff. on one--
I thought you could just turn the whole tank around but I see gary's method is just moving the tank "innards" around- shorter fuel line route I guess-
Run 5%, and I like the OS-8
Burn and turn-