On my 68 Autostick that I am restoring their is a metal line that was on the passanger side under the running board. The end near the front of the car is a connector (looks like a spark Plug) that has a small hole in it and connects to a mteal line that runs the lenght of the car. The back end was cliped off so I do not know where it goes. My other bugs do not have this. My first guess was Gas line but I don't think it is.
Thanks Steven