I think they are all in pasterboard, but Im unsure. Some are in what I thought were external walls (brick on the outside) but I dont know if theres plasterboard on the inside if that makes sense. I like the drilling idea, thats a good shout- Ill get a massive drillbit. And a drill.
You might find that once the drill bit catches it rips them out anyway. You'd only need a HSS bit slightly bigger than the central hole, not the full diameter of the metal disc.
I think they are all in pasterboard, but Im unsure. Some are in what I thought were external walls (brick on the outside) but I dont know if theres plasterboard on the inside if that makes sense. I like the drilling idea, thats a good shout- Ill get a massive drillbit. And a drill.