All three images there are variations on Anguirus, even that really bizarre, insect-like one on the far left! Also worth noting is that it was not for Destoroyah but rather the unused "Godzilla Vs. Ghost Godzilla" concept that was tossed around at some point (but it was in the Destoroyah section of the book, hence my initial confusion!).
My apologies for not scanning the image but it was so close to the inside margin that I would have had to crack the spine of a beautiful book to do so! Also, my apologies if this is more common knowledge than I have been led to believe!
Source: My friend's copy of the
