Its easy. I fitted 3 gauges into my car. Oil pressure, oil temperature and a soon to be used boost. I just ran the wires through the same location the wiring for the ECU goes into the engine and then along the bottom behind the dash to the gauge. As stated above you need an oil sandwich plate, this simply fits between your oil filter and the engine block. the sandwich plate is already threaded so it screws in where the oil filter used to screw on. Then the oil filter screws onto the sandwich plate. So you need to it when changing your oil. Then the temp/pressure sensor screws into the sandwich plate. Simple.