Mopar Low Oil Pressure Switch

If I recall correctly;
a wire goes from the sender to the positive side of the coil,
and grounds the ignition,
in case of low oil pressure.

It also will not let the engine start till the oil pressure
builds up to at least 15 lbs, if I recall.

I bought one of those in 1979, not sure if it is in the cave
{cellar}. LOL.