Huh? Mine must have been drilled at some point by a machinest. That's where my oil pressure guage is.Both holes have threads but no oil passage hole on the upper right and left of the big hole. I guess I will get the fittings and use the big one.
The port slightly above and to the right in the attached picture is also an oil port. This is typically the one that is used becasue it's a smaller port and more easilly fits the line you would be using.Can you run oil pressure gauge to this or is there another port for the gauge ?