These? The wiring was a bit confusing as the colors in the instructions don't match the ones you're tapping into. I had to use a Multimeter / a schematic and probe around for a bit to make sure I had it right.
I would drill into the chassis for that ground wire. At least sand it down a bit so you get a good ground connection. I did not and The black housing that the wires go to (with the kit) squeals if I turn the potentiometer to allow the brightest blue. I'm pretty sure it's a ground issue.
I also recommend using some type of adhesive to keep the white insert down. The speedometer needle gets stuck sometimes:/ I had to tape the insert down. Otherwise it looks awesome.
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