Breather tube. What did I win?
Unless that Lincoln dates back to the early '60s, it doesn’t have a breather tube.
A PCV system was mandated, beginning in–I think–1963, so I would say that the part in question is the PCV valve and its related “plumbing”.
The breather tube or “make-up air” line is connected to the air induction tube between the air cleaner and throttle body. The PCV line is connected to the intake manifold where vacuum is present.
I named mine “Phil.”
Oil filler cap.
That’s the PCV breather tube. The PCV valve is in the passenger side valve cover and the breather tube connects to the driver side valve cover.