Supercobra,
If you are running a single 4V carb, the isolator location in the photo is great. I'm running dual quads with banjo fittings to the carbs that keeps the fuel lines inside the linkage and had to move the
oil tank slightly outboard so my isolator plumbing coming off the back of the second carb cleared the
oil tank cap. Depending upon your setup, you may want to rotate the isolator 90 degrees from the one in the photo. In any case, the isolator is hidden very well under the
oil tank. Good luck and don't drill holes in the firewall until you are sure of the location and what is on the other side.
Jeff