Yes very good advice..... I might go with the pipe (PVC) as you mentioned so you can drive in a 3 foot fence post, the green ones you can getI have read several different how to's for these ghouls over time. It is common for the back portion of the under structure that supports the hood to be made out of Monster Mud with chicken wire frame. You can also use a paper mache type material if you want them to be a little more light weight but this would be less weather resistant if they are going outside.
If you are planning on putting them outside, building them on a pipe that can be slipped over a steak driven in the ground will avoid the need for the H supports.
This helps add to the floating effect in a close up situation...