I just found out about the potential Castle Grayskull playset for MotU Classics. Looks interesting. However, I keep running into a claim along the lines of: "The original castle had a secret door sculpted onto the side." I've heard rumors like that before, yet after thirty years I've still not found this mysterious door, nor have I been able to discern any proof of it in the one image of the prototype that I've seen. Will someone please show me where it is?