I wired up a radiator fan indicator.
I popped the cover off of the fuse box under the hood and found the fan relay. Actually, there are TWO of them, and I was befuddled on which one to use. A Fluke meter and some probing gave me an idea of which leg to trap the wire under. I notched the cover so the wire wouldn't get pinched when I put it back on.
There is a row of pop-out "buttons" to the left of the steering wheel. One of them has a little coin holder, the other two are blank. I bought an LED assembly from Radio Shack. Then I drilled a hole for it in one of the blank buttons.
Then I ran the wire from the fuse box to where I had popped out the buttons. Many bad words were said to get the wire to this point.
I crimped on a ring terminal on the ground lead of the LED assembly and attached it to ground, and used a crimp connector to hook up the red power wires. Then I snapped the buttons back in the dash.
Now for that gaping hole below the bumper...
Yeah, I know I could just watch my ScanGauge to monitor coolant temperature. And I do. It runs at 181 by the thermostat. The fan comes on at 204. I'd like to block off the lower opening as much as possible, to the point it hovers around 195 on the highway. (Not much in-town driving on my commute.) The light will help me determine the smallest opening I can get away with.