Buz Sawyer Daily Strip Art from September 21st, 1988 by John Celardo

Nice bonus! Celardo is known mainly for his Tarzan strips, which he did a plethora! This was done on Duotone board for shading special effects, so you're seeing the bleed through on the backside from the chemical applied. 

Looking at your additional image closer, I do believe you are right about the image being transferred from another strip. Maybe he stacked these before fully dried? 

Fantagraphics put out a few volumes of the initial Roy Crane strips from the 1940s.  I picked up the first two volumes on a lark eight years ago and thought they were decent.  I had no idea until a certain dealer started giving these away that the strip continued in the 1980s as I can safely say that my local newspaper wasn't carrying it then.  Celardo's work looks nice here, but your guess is as good as mine as to whether the strip was worth reading in 1988.

If you have a lot, then be careful with handling these too much.  It gave one dealer an allergic reaction and they had to wear gloves for a while.  The acidic properties of the developer solution remain after they are dry which is the reason when stacked, the image transfers onto another duo tone board.