Woody, that could have been a revision when they added the 102 gal. tanks in each wing. I don't recall ever seeing refueling points in engine nacelles. We need an actual picture of a non re-fitted LE 10 to see where they are. I don't have time to do it today, maybe you could find one or someone here already knows where one is. In any event those pictures are encouraging.
Doc, here are some pictures from the internet showing other L-10 Electras. I have not been able to find any signs of fuel fillers on the wings of any of the aircraft. On some of the pictures, the fuel filler door on the
cowling nacelle does show up.