Instead of doing the traditional single list of favorite OPs, I’ve decided to sort it by decade. Technically you can consider this my favorites of the 70’s and earlier, but the actual top 10 are all from that decade. (The older one that came closest to making the cut was the opening to Tiger Mask.)
10. Science Ninja Team Gatchaman, “Gatchaman’s Song” by Masato Shimon and Columbia Yurikago-Kai
This is actually the second opening…and the same song as the first ending. For some reason, the first season of Gatchaman used the slower “Defeat Galactor” as the OP and “Gatchaman’s Theme” as the ED; later seasons switched them and the songs definitely fit better that way.