On an unrelated but interesting note, I was able to locate a full sized photo used to make Primo Carnera's card for the set. What looks like hash marks below the name is actually the photographer's stylized signature: Chas. Heath.
Charles Heath was a Los Angeles-based photographer known in sporting circles as having served as Jim Jeffries' official photographer at his facility in Burbank, the municipality right next door to Glendale, where Carnera operated a liquor store. Since Carnera was wrestling in the 1940s-1950s to make ends meet and was based a few miles from Jeffries, I suspect that when it came to publicity photos Heath was the logical choice. Here is a stamped, ink-signed Heath original from Jeffries' facility:
