filler spout restrictor???

[sixtysix]

I tried to run a plastic tube down the filler spout to my main and aux tanks to siphon the gas out so I can drop the tanks for cleaning. The tube always seems to hang up before it gets into the tank. I even tried tapeing the tube to a metal fish tape thinking the plastic tube was too flexible and causing the hang up. Still no go --- is there some sort of restrictor in the filler tube thats not letting the tube to go through? Would like some advice or ideas.
THX - Rick

 

[eds66bronco]

disconnect the line at the sender and siphon from there.