Well, I finally ended up submerging the entire thing. It has two air leaks – one is under the backing plate near the spit drain. The mouthpiece end has two more screws and is not leaking. I’ll take the back off again, but I anticipate I’ll finding some new gasket material for it.
The other leak is coming around the first “G” – streaming out both sides. This could be gasket, too, I don’t know.