Idiot light with gauge
I recall seeing that mod but I dont recall the details. All 3 gauges are calibrated about the same. Main difference is the screens. So a temp or fuel gauge could become a oil gauge.
The hash marks on that gauge he used are identical to the fuel gauge screen. How he changed E to L, F to H? How he got "oil" in front of the gauge? Some custom decal printing I presume.
