Oil pressure sensor is electronic and supplies a signal to the PCM which in turn, relays it to the BCM via the class 2 line and feeds the signal to the IP cluster. I guess you could remove the electric sensor and install a pressure sensor for a gauge. However, this will turn on the service engine soon light since the PCM no longer sees any oil pressure and might put the vehicle in a reduced power mode, or maybe even a no run mode.
I would go with USMC_TOP and get a scan gauge.
And most of the sensors used on modern vehicles are pretty darn accurate. Problem with most is that the actual gauges in the clusters are not that accurate. So a reading from a Scan gauge should be accurate. Great example is the coolant temp gauges can be a little off at times.