[Fot] Oil Pressure warning lights?

[George Harmuth]

I've been thinking about putting a low oil pressure warning light on the
dash of my Spitfire race car. I have full mechanical gauges but I'd like
something to bitch slap me if I miss a pressure drop.
Does anyone have any specific recommendations for sensors, lights and what
PSI the system should be set at? How about water temp, anyone running a
warning light for that too?

thanks
mike