Hello.....My question is this??: I have a 72 Polara 440 police package with the oil pressure "light"....I was given an NOS oil pressure gauge by a great friend.
To install it I need to swap to the correct sending unit BUT the new NOS gauge has two (2) terminals on it.
One is for the sender but the other I am not clear...is it ground or 12 Volts input or 5 Volts input from the dash cluster?...I assume it would be 5 volts positive input but I want to be clear before installing.
Also looking at it from the back...which terminal is which (sender/voltage)?

Thanks in advance.