Chick, in my experience the tank straps have all been painted black regardless of the LOS or NOR plant. The blackout on the bottom of the tank was done after the tank was installed in the car. In my example pics, the upper part of the tank strap does not show paint while the rest of it does. I can only assume the original black paint on the strap was not thick enough to keep it from having rust form after this many years but the extra black when the tank got sprayed was enough to keep the rest of the strap looking black.
