The brake booster line is by far the easiest to tag onto. As far as power, in the wires going from under your steering wheel you can splice into a wire, not sure which one I'll check when I get off of work, but if you use a wire tester you can tell which one to splice into by seeing which is hot when your lights are on. This way the gauge will only light up when your lights are on, so it's not on all the time
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