That was pretty hard, and I wasn't sure at all! I just have that block in my head for some reason (the triangular one, I mean), but it was in a different place then I expected. There's not much else in there that's distinct besides the ledge, which kind of implied GT to me. And the rock, which is a little darker/grainier at that spot. But you really did have me wondering!
I think the goggles in the picture take it from "whoa, you're a masochist" to "insane fun"