hey guys - i should have got one a while ago, as these gauges are hard to find - looking for the complete set-up, with sensor - shipping to seattle 98115 - thanks for looking, brad

p.s. - are these voltage specific?

I'm using the Micro 1000 Dual CHT gauge from Aircraft Spruce. No issue with voltage as the thermocouple generates the power to the gauge. Have it on cylinders 1 & 3 going on 4 years with no problems. It's best to grind the head around the spark plug to allow the sensor to fit better. It works without doing that (how I ran mine for a couple years) but you risk destroying the sensor when changing plugs. There's a thread here with pics of the installation. Below are a couple pics of mine:
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