Sometimes the number of parallel error and variations to chase may get annoying, but this is one card release I greatly enjoy the chase for all of them.
1969 had several known printing errors that caused variations to chase in their,release. One of the more famous was the player name color swaps.
As you can see from the 1969 Topps Gaylord Perry card has two versions to chase. Images supplied by TCDB. The yellow last name is the corrected version, while the white version is the lesser available version.
The same can be said for many other players including Reggie Jackson.
Above you can see the white team name color swap version next to the base.
The back makes the color swap version known by placing an identifier of the parallel by the card number.