1951 Oil bath air filter refill

[51shoeboxer]

I dumped the oil out of my oil bath air filter, cleaned everything in mineral spirits and let them dry completely. Then I put fresh 30 weight motor oil into the bottom of the two-piece oil bath filter, but the amount was rather ambiguous. There was a "fill" line, but it is close to a ledge in the bottom half. I added what I think is the correct amount of motor oil, but I am left with this question: should the top part of this two-piece oil bath air filter dip into the oil in the bottom half? Before cleaning this filter, the top half did not dip into the old oil that was in the bottom half. Thanks for any advice you can provide.