Simply unpick it from the inside and gently pull it round the door and then from top to bottom.
As it turns out, they came off really really easily, probably as the weather has been so hot, and they simply peeled off. It didn't leave any glue residue at all, although petrol or turps would have cleaned it off.
The back door 'B' pillar side needs to have some plastic trim removed first but that just pops off.
The picture shows before and after ( hopefully ) and I really like the look with the black removed. Thanks to Midsdaz
