Upon taking the bottom off the air cleaner on my 51 cab over I noticed there wasn't much oil in it probably cause there was a pin hole in the bottom and noticed a bit of condensation in there as well. Fixed the pinhole and went to fill it with oil but wasn't sure if just the top section gets filled or if the whole pan gets filled to the oil level mark. Seems to me the whole thing gets filled but just want to make sure. The repair manual isn't to clear on the coe. So I figured I ask the pro's. Thanks