You have a flickering oil pressure light at idle? That's not something you should first blame on the sensor.
First do a 5W-30 Valvoline Full Synthetic High Mileage with MaxLife oil change, including a new Motorcraft FL400S filter. Correct viscosity, correct level, and clean filter ensure correct pressure.
Still idle oil light sometimes coming on, even moreso when hot? More than one second of oil light at startup? Then you should start suspecting bearing clearances if you've never done rod bearings. Also you have oil pan pickup tube (clogged screen?), leaking pickup tube gasket, and an oil pump on the front of the crankshaft as possibilities.
You can replace the sensor just to be sure it's not erroneous, but it is more likely that it malfunctions and doesn't illuminate.