Ok, I'll admit it, I looked at the pics of the tape before reading anyone's posts about them, and I saw - nothing.
I looked at them again as I read each post giving a different possible location and only on one did I see something that I could consider resembling a heart shape but I certainly wouldn't have described it as a perfect heart shape and would have described it more of an impression on the tape than as sticker residue. I see the outline that someone put on the pic but if I look at that area of the pic without the outline, I cannot see it.
But, hey, my eyes aren't what they used to be - so nevermind that I can't see it and am confused by the fact that different posters see it in different locations and on different pieces.
Maybe someone can help me understand how the residue could be showing in pics taken by the FBI when the FBI said they couldn't get it to show up? (I'm pretty sure that I saw an FBI tag on the photo so it appears they are the one that provided these photos.) Are we concluding that these were pics taken before the analyst said that and someone else at the FBI had already captured it? Are we concluding that someone else - perhaps a better photographer was consulted at the FBI & took them after the one wrote that it couldn't be captured but before it was destroyed by fingerprinting process?