Keep working on the "brownie points." My wife started out luke warm on some of what I'm trying to do. She used to pick on me a little for driving slower than the posted speed limit (50 - 55 in a 65, driving in the slow lane), but as I kept at it and my gas mileage hovers at 40 with NO mods whatsoever, now she just enjoys the scenery and we chat while others blow past us. She doesn't even miss a beat anymore when I take it out of gear because "when gravity outruns aerodynamics, we should coast."
Improvements around the house are the same way. The power strips on the microwave oven and the entertainment system took a little getting used to, but a lower electric bill made that pill easier to swallow as well.
Having more disposable income makes a great arguement. Keep up the good work! Every dollar you don't spend on gasoline, you can spend on your family.
