Yes thats it. I was wrong about the olong oring, it has 2 orings the oil must pass into that cover and back out. Go to page 114 and you can see the 2 orings under that cover. Also if you hook in there you well not be able to use the remote valve and the 3pt at the same time. That part I think would be the same even if you pick up your hyds from the hyd block.
Let us knowI vaguely recall that from the manual... I'll have to read it again.