Gasoline flow

[1939Deluxesedan]

I have tried to blow out the gas line without success. The drain plug was buggered up when I got it. I don't see anyway to drop the tank with the body sitting on the frame. I'm not sure what to do. Can someone suggest a aftermarket tank? I thought about one of those cameras on a snake to look in there. Maybe its all rusty. In addition to blowing compressed air toward the tank, there's a break under the drivers side floor with a rubber hose section, maybe it was a filter there at some point. I even tried to pump compressed air into the gas filler with a wet rag over it to make a seal. I poured about 2 gallons of gas into the tank. Maybe I need more.