gas tank filler neck issues

Just like 66dartgt described. Here is a pic of the backside of my '72 Duster. You can see two sheet metal screws, and also additional holes in the body. I figured that maybe they used a couple different suppliers of the filler tube, and to make the cap line up correctly outside one tube was mounted diffferently?
In any event, 66 talked you through it.
C

Aug29,2007 023.jpg