1925-31 Exhibit Post Card Back Printing Color Question

[Rascal1010]

I have been a collector of Gabby Hartnett for a number of years and have slowly been assembling a set of his Exhibit cards. I have run into a questions on his 1925-31 Postcard backed exhibits. I know that there is the photo background and the extremely rare silhouette version of this card, but my questions is if there is a red printing variation of the photo background cards? I have been able to obtain the Green, Yellow and B&W versions for my collection, but have yet to ever see a Red color variation, just wondering if any of the more experienced Exhibit collectors know if the Red color printing extended to the entire checklist of cards or if it was only used on certain cards? Adam's book as great as it is, unfortunately shed no light on this question on how the color variations were applied to this set.

Since all new posts should have cards pictured in them, here are the three color variations of the 1925-31 Hartnett postcard back that I have in my collection.