You might need to rejet if you intend to run on pure ethanol, but distilling your potato hooch is going to require a lot of energy. You'll probably end up paying as much to your utility provider as you save at the petrol pump.
If money's that tight, switch your diet to one based on baked beans: they're cheap. Plus, if you drill a 2" hole through the seat of the Fazer and add a short length of pipe to the airbox, the resulting methane emissions will usefully enhance the mpg figure.