From memory the trim on the “A” pillar is riveted in place, so you will have to drill out the rivets to remove the trim. I used small stainless steel screws when I put mine back together which worked out pretty well!
Are you referring to the Chrome Windscreen surround ? If so, why didn’t you mention it before I came over to Belgium last week – I’ve got a spare I could have brought over for you !!
As David Wardale @robertdavidwardale says, these are riveted in place – they are easily drilled out and replaced by a small screw. What you do need to be careful of is fitting, to make sure you don’t put a bend in it as you won’t get a crease out.