Found a metric adapter and picked up and installed a mechanical oil pressure gauge. Cost of materials was about $20, time to install was about an hour, peace of mind, priceless!
There isn't much space on the dash, so I placed it a little low, and on an angle right next to my "cruise control". The gauge confirms what I found with the other gauges. Oil pressure is right around 50 psi. Stupid idiot light.
Your dash looks a little different than mine. The surface you have your gauge mount mounted to on mine is further towards the front of the tractor. If I mounted it to that surface I wouldn't be able to see it under the dash.
Instead I put my mount right under the light switch and 90 degrees rotated so it will be facing up at me. I may bend the mounting bracket so it angles down a little.
Unfortunately I didn't get the gauge itself installed because the m10x1 brass tee I bought won't thread into the engine without forcing it. When shopping for parts I tried not to notice that there apparently are M10 tapered and non-tapered. I suspect that the Kubota parts are tapered and my tee is not.
My Kubota pressure switch seems to happily thread into the female portion of the tee until it abruptly stops. I assume if the male is tapered and the female is not, as long as it doesn't bottom out it should be fine for holding pressure.