Weird Gasoline Leak Today. Thoughts on Cause and Source Appreciated

It's the vent and it's doing exactly what it's supposed to do. I'm not familiar with the fish body but I'd guess the vent does not elbow up "quite as high" as the other A's. The conventional bodies, the vent leaves the filer tube and loops up pretty much against the underside of the top of the quarter panel, then back down. So you'd have to get them REALLY full to get them to siphon much out. The filler is designed as a "vacuum break" so that as soon as warming fuel is pushed out down to the vent connection, it "breaks" and stops