Just as an aside, today my family and I begin our vacation road trip to Reno, Las Vegas, The Grand Canyon, Utah, and spots in-between!
Our first selection today is Sgt. Fury #64 and the reprint in #161. The only change I can see is that the word "The" in the bottom blurb has been redone. I can't decide if I prefer the single-color original or the multi-colored reprint!
Next, it's Avengers #42 and the reprint in Marvel Triple Action #34... an all-new cover, yet based on the original's layout! Looks like some elements were re-used, like Hercules and Dragon Man's heads!
I definitely prefer the coloring on Fantastic Four #81 over the reprint in Marvel's Greatest Comics #63! I don't detect any art changes other than the relocation of the blurb, though.
X-Men #37 doesn't seem to have been changed much, other than coloring, when it was reprinted in X-Men #85, except possibly shifted a little to the right.
When Fantastic Four #42 was reprinted in Marvel's Greatest Comics #32, there were two changes made: The Torch's figure was moved up, and the biggest blurb was moved. Oh, there's another blurb that was eliminated entirely, so that's three that I see!
I've never gotten why Sgt. Fury started getting reprinted in Special Marvel Edition, when the book was mostly reprints by then anyway... But as it is, here's Sgt. Fury #13 reprinted in SME #11, and as you can see, the image was reduced a little bit and shifted down.
Amazing Spider-Man #152's cover was shifted down a little for the reprint in Marvel Tales #129, but I don't see any other changes.
Similarly, when Sub-Mariner #11 was reprinted in Tales to Astonish (2nd series) #11, the only change was in the coloring, a bit less monochromatic than the original.