This pic shows most of the fittings used for the oil tap in the back of the head. The one wrong fitting is the Tee. I use a 90 degree elbow.

But since I was out of stock on the 90 degree elbows when I took these pics, I substituted the Tee. Just to be able to show the general layout.

When I do this oil tap for a 700 motor, I use the tap to monitor real oil pressure during the run-in procedure. And then I remove the oil gauge and install the plug. The oil tap is in place for when the customer installs a mechanical oil pressure gauge.