We have been given two clues about the origin of this photo:
All right, so that’s Don Kessinger applying a tag to Dave Kingman. You might think this one’s difficult, but really, it wasn’t.
That’s a Giants uniform Kingman is wearing, so that narrows it to 1971-74, the years Kingman played for them.
Further narrowing: Kessinger is wearing pants without a belt. The Cubs didn’t start wearing those until 1972, so that eliminates 1971.
Kingman played 16 games at Wrigley Field from 1972-74. There’s ivy on the wall, so that eliminates three of them, games played on April 24-25-26, 1973.