I get about 80 under a load too and about 20 to 30 at idle too. I made 2 of those gauges one is on my bike the other is on Wendy's. The parts should be easy to get I just mentioned J&P because that is where mine came from. The odd double banjo bolt is probably the worst of the stumbling blocks. I realize most guys don't have a lathe to spin one. I used a chrome 10mm banjo fitting with an AN3 fitting on it to accept the end of the braided stainless brake line. Then and AN3 adapter to change to 1/4" pipe then a chrome elbow and the gauge into that. An easier way might be to run the line from where the oil sensor is now since that is already a threaded fitting. Put a T fitting there and you could still keep the oil light too. My oil light still works too since I went off the banjo that is on top of the trans. I just don't want to depend on that oil light.

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