Checklist #527 with #105 Kevin McReynolds and #719 Keith Miller has two variations one of them has a grid type pattern around the two numbers.
I don't know if it has something to do with when they made the correction but it shows up better in hand then it does in a scan. A few of both can be found on COMC.
91 Topps #527 variation.jpg
91 Topps #527 grid variation.jpg