Twenty-seven stickers in the first set.
One sticker per team for the large logo sticker series.
The back of each card has a history of the team who's logo is featured on the front.
There were no variations in the large logo sticker series.
However, there are variations in the smaller 4-team stickers.
There are actually only 12 cards in this set, but I'm showing 17.
You can see that several cards have the same 4 teams on the front.
That is due to there being multiple team history backs.
For example, on the last two cards shown one has a Pirates back and the other a Padres back.
This is the complete set including the variations.
Thanks to Fleer Sticker Project for documenting the variations.