Just a quick look at the skulls i have re-sculpted from the original 'basic' plaster copies so far.
As for the faulty (my fault) screaming skulls i have one almost completed. Just some minor touches to sculpt now. This one of two so far made has come out better than i thought it might. Whilst this is definitely one design for the gas mask skulls (see previous posts) i can now or rather later remove the plasticine mask(s) from these skulls & still have a working fairly decent screaming skull in then end.
Just goes to show never rush to give up on a project, you just never know how a mistake can be salvaged until you try.