What am I missing?

On my 74 dodge dart sport, its missing the screws that hold the filler tube in place to the body. Also I'm not sure if I even have the right locking gas cap on it.. it looks small because the screws show even with the gas cap on.. So here are my questions. What rubber seal goes on in between the body and the metal flange? What kind of screws do I use? And do I have the right gas cap? Any pictures of what it should look like will greatly help me out!