That's an excellent DIY, as good as they get. I did mine in about 2 minutes on my lunch break at work. It's been raining here like crazy and the car fogs up fast. When I switch to defog, I hear that AC compressor kick on and it makes me feel sick.
I've gotten 39.5 mpg on a tank without running the defogger/defroster and on the next tank when I turned it on, I only got 34mpg. (All my driving is highway, BTW.)
