F100 Siphon Preventer??
 

I want to use my seldom drive '67 F100 as a back-up source of gas for my lawnmower and generator. I bought a cheapy tube and pump but my truck has a spring like thing preventing the tube from going in the tank. I can't believe this was stock in a '67. Is it stock? Any other comments.
Thanks,

Well, my friend came over, opened the door, removed the rubber filler tube, and ripped out the spring. All done in 5 minutes. Now I can siphon out of my own truck. But since I don't have a locking cap, others can steal my gas too. I hate it when some guys make it so easy.