Thanks Andrew, great advice. Yes it's chromed and I live 3/4 mile from the ocean but didn't see any visible corrosion peeking inside the broken section, only slight surface rust around the broken edges, no vent hole either. It does look right about where the drop out plug end would be as well. I wouldn't be surprised if the tube was overheated during the build as it didn't appear to be built by one of Bob Jackson's master builders. Oh, and the dropouts are chromed, not stainless.