I've got three fills of "average" riding, not too fast, not too slow, some commuting, some weekend riding with my son, no serious hypermiling.
The average of these fills is 3.49 l/100 km (67.4 mpg), I'll use this as the base line to measure any mods against.
I've got the fairing mounted now and the new sprockets have arrived.
I'll probably play around with the height/angle of the fairing for a while before fitting the taller gearing, so I can see what works best without confusing the issue too much.
I haven't been riding as much as I'd hoped, we've had a very wet end to this Summer.