HELP!!!

I've got a zetec 1,8 -94 which today is wired up with the original ECU and associated senders. Before starting it up for the first time (hope it'l be in a few days) I want some way to monitor the oil preasure. My question is if it's possible to use the existing switch? at what preasure do it open?
Do anyone know if the signal from the switch is used for the ECU or if it's just connected to the oil preas. lamp ?

All help is most appreciated!!

BR //Bernt, Sweden

Mine is just wired up to a light, works fine.

why not get a propper guage.
Twice in my life I've had to have a car towed because the pressure switch had failed and the light came on.