Removing screw from port to install pressure switch

[wetbirks]

Can somebody tell me what will happen when I remove the screw out of the oil pressure port to install an oil pressure switch? Will oil come out? Do I need to drain the oil first?

Thank you

[Peter]

No need to drain oil.

A tiny amount may come out

Peter

[Al Schober]

I hope this is obvious, but DO NOT do it with the engine running.

[wetbirks]

Finding this screw to be very hard to remove! I will need to try some new tactics tomorrow, perhaps a slot bit in a ratchet for leverage.

[Al Schober]

I use an impact screwdriver to get them out. This is the type you tap with a hammer, not a power tool.
I prefer the pipe plugs with a 3/16" hex socket. In brass, they're McMaster p/n 50785K112. They're also available in stainless.