BIT:
Here's an unmarked copy of the photo I used. The only thing I did was run it through PhotoShop and "equalize" it with one click and reduced the size to make it easier to see. As I mentioned in my writeup, this could be some graffiti put up by someone later on and for some screwy reason. But, here it is. Look at that shadow. Perhaps the number "2" to the left has nothing to do with the shadow drawing.
Sorry, that figure on the top left doesn't look like an eagle to me. I see the eye, but there's no eagle-beak to go with it. The "face" is too rounded.