Hey Justin-The oil can does have a type of vent in there to help seperate the oil from the gases-I cut an alcohol bottel in half and used the top half on my pipe below the lid. I'm wondering about a small engine muffler instead in there and I'm thinking that might be the way to go.
On the subject of knobs for the cover-I did a Google search for metric knobs and found a company on line that sold them to me-it's been some time back now-but there were many companies that had these parts. There was one in particular that had them, as solid aluminium parts and would look great on there but were a little to expensive for my blood.
The studs were easy enough-went to Lowes Hardware and found 6mm bolts about 2 inches long-cut them down to the size I wanted, with my dremel tool an put a couple of hex nuts on, locked down tight on them, and installed with a socket wrench. Oh yeah wrapped the bottom of the with teflon tape for sure.
Thinking about the vacuum gauge-if I cut the panel out for the pod to come through and just that part-may make it even neater.
Thanks for the responce
Poolman