1972 dodge dart with oil light flicking

I have a 65.000 mile 1966 /6 and it has never showed the oil light except when I start it and as soon as the pressure came up (2 seconds) then stayed off, Till one day a week ago The light came on and stayed on then I shut it down and pulled the wire off the sending unit on the side of the engine and cleaned the brass clip off and plugged it back in,,,, Scared me to death, you could just have a bouncing wire and a loose connection on the engine block sending unit .. True happening and all it was was a loose connection