Hi Ted,
Perhaps we are splitting hairs, but I don't consider any cards with ad's on the back as proofs... I have always thought that Wagner and Plank were probably on the same sheet, but I have never had the evidence to prove it.
As far as the printer's mark goes... I have several examples of T205's and T206's with the same marks on more than one side. I will try to post a few when I have time, but anyone who owns an Irv Young will see these marks on 3-4 sides.... Be well Brian[IMG]
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