Good luck. I can relate to your skeptical friend. I thought hypermiling might gain me a few mpg, so I am thrilled to get 30% over EPA. 45% is a pretty arbitrary number, but I guess it might be fun shooting for it.
As for instrumentation, I shelled out for the SGII, but I think anything with instant and average mpg would be a big help. Even if it's not 100% accurate, making the numbers go up is the name of the game
