R1200R oil pressure gauge instal

[TinkerToy]

Looking for info on the instal of a oil pressure gauge on my R1200R...my thinking is one could remove the pressure switch and tee in a gauge sending unit and still maintain the original light switch...any problems with this?...what is the original thread size, diameter and thread pitch, of the now present stock pressure switch? Where is a good starting point [source] for the metric fittings needed? I'm ready for the good, bad, and ugly comments...why the addition of a oil pres. gauge...just cause.