If in case I don't have a proper understanding of the Lincoln vent system, please accept my apologies.
No, it seems you have a better understanding than I do ...
That is the fresh air intake on the front of the valley cover (filtering media).


There is no baffle directly under it, although there is an air deflecting baffle midway same as the FYB. This allows airflow to enter the top of the cylinder heads, so front to rearward air flow must be the same as a FYB?
The later HT 302/332 shows a rear mounted draft tube.
The front mounted oil filler tube/road draft (6758) allows oil fill and road draft so there must be baffling in that canister.
I have a 1957 MERC WSM somewhere. Let me find it and see what the CCV flow chart shows and will be back.
This changes the above suggestion for PCV modification.
THANX FOR THE WAKE-UP CALL!