Nice schematic. The relay really isn't necessary; you can use an SPDT switch to change from one sensor to the other, or a rotary switch to change between multiple sensors. The sensor is just a thermistor (a resistor genetically engineered to have a lot of sensitivity to changing temperatures). You will want to test the sensors at various temperatures to make sure they read the same or at least determine the error from one to another, shouldn't be much more than a degree or two. Others have stuffed the 124 readout into a 123 instrument cluster, using the spot originally designed for a "PRND2L" column shift display. If it doesn't fit, I have a 126 display that might work.

Jeremy

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"Buster" in the '95

Our all-Diesel family
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