The stars shake in their courses. The earth trembles. The shape of space is warped. I think there's a small possibility Frank may have made a mistake. Only a chance, you see, since I've never actually taken an OP gauge apart, or the sender, and I don't have any manual for the wiring diagram but the one for an 89, but I think the OP gauge and sender work off 12v 'lectrons. Only the fuel and water temp gauges work off the voltage limiter. I don't dispute the possibility of warping the bimetals anyway, tho...

My experience with the stock gauge is that in addition to being purposely overdamped to the point of limited utility, it has a sender that deteriorates, either with a leaky diaphragm, or with a deep fried internal rheostat thingy, and either reads low (part of the pressure leaks out thru the sender onto the motor and ground) or not at all, or with dead spots in the range. There is no real substitute for a good mech oil gauge. Plus a low pressure alarm of some kind.