I agree that the panel would not receive anything other than an "A" since some of the right border and bottom corner are missing. The same could be said if there is glue or scrapbook remnants on back. I see where you say that none of the grading companies will slab it anyway, which I assume means you inquired. I would have thought otherwise if the measurements were within a slab they already use, such as an m101-2, which Beckett and PSA grade. It would be ironic if they would slab a six-stamp panel were you to cut off the far right pair.
Personally I agree with those who say don't chop it up. Value wise these are not high dollar stamps as it is, and the grades--if you survive the dreaded "A"- are generally harsh. I suppose they could appeal to a registry hound, but otherwise they likely will not fetch that much, IMO. Preservation is important of course, but authenticity is not really a factor--no collector is going to think someone faked a 80 something year old newspaper. Keeping it intact may someday prove to be wise from a value standpoint, as these may gain popularity when the hobby better appreciates their scarcity.
Here is a somewhat recent thread on these stamps you may not have seen-- note that post #12 contains a panel similar to yours, although with only six (different) players. Perhaps that forum member has some ideas on preservation and value related to his experience.
https://www.net54baseball.com/showth...ighlight=OMAHA
EDITED TO ADD: looking at ebay, I see where even low-grade super HOFers are listed at 4 figure sell prices. If the market is supporting anywhere near these values, then I stand corrected on my earlier statement that these are not high-dollar items. I don't want folks to think that I consider such prices as nominal
I have not researched prices realized but thought they were far less than four figures.