Watch out on those Autometer mech gauges. The oil pressure gauge is 1/8NPT. People try and force them into the port where the stock oil sensor is, but it's 1/8BSPT. Sometimes it works, sometimes it doesn't.

I always used the Defi stuff. Their sensor comes in 1/8BSPT and screws right in to the oil filter housing. Run 3 wires and done. Never had their sender die on me either.