I don't think you're going to find a premade line long enough at the auto parts store, so I would just get a 10, or 25ft roll. If you're going to mount the line back in the tunnel, you may want to cut some windows to add some additional anchoring, instead of just letting it flop around inside. A lot run new lines around the outer perimeter of the pan. If you go outside the tunnel, you could piece a few shorter sections together (with the appropriate unions) to make it easier to route. That's what I did recently on a buddy's 67 Beetle.