Actually, those are Jackson's stats on the back. It's just a shift in the printing on the back and then when it was cut, it wasn't lined up properly. There are probably another 131 cards out there like this (the sheets back then were 132 cards per sheet), but many of them could have been spotted before they got out in packs.
-- Dan --
Note: Please see my profile for more info regarding trading (section updated 10/25/2023). I have added a large portion of my inventory to the site, and currently have trading turned off (details are in my profile). I have (finally) unearthed my 2 very large boxes of Star Company minor league sets and they are available (email for details).