Looks like the seal is sold in this diagram at #9, correct?If you look at the diagram, you can see the tubes are sold as part of the head. So if there's a lower seal, it's not intended to be field-replaceable.
You are referring to the tube and not the seal, correct? The seal on the valve cover should be easy, right?I'm 99% sure the tubes are press-fitted into the cylinder head. In other words, they're permanently installed and sealed, and it'd take a lot of effort and cussing to get one out if you had to for some reason.
Yes. The tubes are pressed into the cylinder head at the bottom, and sealed to the valve cover at the top with the small round seals. Those seals are not glued in any way to the valve cover -- they fit into a "lip" in the valve cover and you can pretty easily remove them and install new ones if needed.You are referring to the tube and not the seal, correct? The seal on the valve cover should be easy, right?