I have now stripped all of the resin casting blocks off the main parts. This is what everything looks like just before shooting some primer.
I had some trouble with the helmet. There was a very large resin casting block attached. I cut off most of it with a cutting disk on my Dremel but some of the helmet itself shattered. I took a small piece of thin plastic card and put it in boiling water so that I could bend it to fit. I then superglued it inside the helmet. This is where I have got to.
As you can see, I have a large area to fill. I am hoping, once the superglue is fully set, that I can now continue the filling with Vallejo acrylic filler and then smooth it all over. Fingers crossed.