update... I installed the gauge in the clock hole, sorry no pics, but needless to say it is a temporary install. I simply fit the gauge into the hole by surrounding the edges with foam insulation. The gauge is lit up now, with the dash wiring of the clock.
The problem now, is that i want to get a gauge that fits into the hole ( 2-5/8" vs. 2-1/16") I am looking at two gauges, but I cant decide. If i go with the electrical one (first pic), the needle will be pointing past the halfway point most of the time and there is a possibility of maxing out the gauge ( i think), and if i go with the mechanical one (second pic) the needle will be pointing at below the halfway point most of the time. I guess my question is what is the operating range that i need to monitor?
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