Yeah I forgot about that one but that's because it never played in the 70's in southern California. I never heard of it until the DVDs came out. Apparently it was an east coast show.
I would never say that about Dragon Ball Z that was much later in the Japanese anime stage not appearing until the 80's. I would say Gigantor was the first successful crossover followed by Speed Racer and Kimba . All 3 enjoyed steady airplay throughout the 70's and were followed by Starblazers...