So if you grade a single issue, then you could see Ewing through the slab. But if you slabbed the 1869 Reds, then that is inside the issue so it would be sight unseen inside? And why stop at the issue, the issues were part of volumes, why not grade an entire volume?
I can see that trimming a woodcut down isn't sensible. but when you have it as wide as the printed margins were, and clear to the top and clear to the bottom, that should be enough.
Realistically, I defer to those of you who have greater knowledge of grading (and that is about everyone).