I checked through the recordings of the original broadcast I have, and it turned out that there are actually two unreleased versions of the first opening animation.
Episode 1 to 5:
Spoiler:
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Spoiler:
Spoiler:
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In addition, I found out a fun fact about the opening song, too. At a certain point in the first half of the series, they re-edited the song for some reason and the Chinese gong sound got replaced.
Version one:
https://www.youtube.com/watch?v=fboaEjIwY2A
Version two (longer gong sound):
https://www.youtube.com/watch?v=gZ9HBmG07OI
The DBox doesn't have version two and the first version is wrongly used for all the episodes. Probably, the people at Pony Canyon and Toei were unaware of the difference and failed to carefully look into the source materials. However, since the movies got the opening song left untouched, DB movie 2 and 3 have version two in the movie DBox.
So in conclusion, there are six different openings to the original DB in total:
1. First opening animation (old Fuji TV logo, shorter gong) - unreleased
2. First opening animation (current Fuji TV logo, shorter gong) - unreleased
3. First opening animation (current Fuji TV logo, eye symbol, shorter gong)
4. First opening animation (current Fuji TV logo, eye symbol, longer gong) - unreleased
5. Second opening animation (current Fuji TV logo, eye symbol, longer gong) - unreleased
6. Second opening animation (current Fuji TV logo, eye symbol, shorter gong [error: only on the DBox])
I will figure out exactly on what episode they switched to the longer gong version when I get more recordings of the original broadcast someday.