'Clean air" heat?, crankcase breathers fouling enginecompartment air Options

[PinetreePorsche]

The first VWs (and Porsches) had dirty-air heat-- the 1950s sealed, 'fresh air' heater-box was a big step forward (and I patched many a Boston-area heater box on split-window vans in my relative youth), well before our Type IV motors came into being. I have a problem, enabling my dual carb-fitted (Webers; the p.o. did it-- it would not be my choice) 2.0 liter to mimic some of these earliest VWs: rapid build-up of dirty deposit on the windshield above the defrost vents and hydrocarbons in the pass. compartment air-- un-noticable in the warm weather, tolerable with the windows open, but a drag- and presumably a health risk- when the windows are up and the heater or esp. the defroster needed. The boxes are like new, and the joints all along the way are all snug. The problem is two different small breathers on the top of the engine, one a couple of inches (center to center) of the oil filler tower, the other about 3 1/2 inches toward the driver from the filler, which is one of three hoses running off a fitting, the other two of which disappear into the sheet metal of the cylinders-- one to each side. Both the short woven- cloth wrapped flexy- tubes coming up from these points are currently capped by what appear to be mini-air filters-- round, well over an inch in diameter and not much taller. Both display wire around their open circumference, possibly hiding other filtering material- can't tell.
SO, my Q's are: Are both these breather-like elements under positive pressure from the crankcase--suggested by the fact that a cleaned engine compartment will be well-bathed in oil after a modest run at near 100 mph-- and more gradually under more relaxed driving? IF so, is there a place on a carbed car for these to disgorge their effluents into a closed loop as in the original FI design. (Or is one positive pressure, the other neg? -which, if so?)
Help me, Obi-wan Kenobi, or anyone else who knows how to channel the hydrocarbon force.