Kevin,

Up under the adapter you have placed over the oil filter stand, there is a barely visible 1/8 npt opening for the stock oil pressure sensor.  In your picture, it appears to be open.  It is hard to see with the adapter installed and can be forgotten till you start the engine.  You would be AMAZED at how much oil can come out of that small hole!  Plug it!  Don’t ask me how I know this!

I think some have removed the heater core tube, drilled and tapped the hole for ½ npt and installed a plug like the one you have in the oil adapter just above it.  I plan to use mine, but I tried to temporarily put a rubber plug in it like you find in the bottom of a boat.  It turned out to be more temporary than I planned.  :>)  At least, it helped to wash off some of the damn oil from the pressure sender hole!

I was told this is where the heater core water comes from.[tube with green tape]  I wish to remove and plug it.   I doubt I'd ever use hot water heat as cabin heat.  how do I do this?   kevin