In 49, the std air cleaner was just the mesh screen. The factory offered the oil bath for extremely dusty/dirty conditions.
The oil bath did a better job of filtering and was more expensive to make, makes sense that it was an option.
My 72 air cooled VW came stock w/an oil bath air cleaner. It also had extensive vacuum and mechanical flap(s) to regulate intake air temps. (warm it up faster). A year later they went to a paper filter. I was told it was for ease of servicing and was cheaper to make.
I still run oil baths on both my 49 Stovebolt and 72 ACVW.
Dave
