Hi Ben73, just used a scratch-pen (is that the word?), make a fairly deep scratch and fill it with paint, let it dry a wipe the rest off, that's all.
edit: use a brush, that's obvious, but before you do, use tape on both side of the scratched line.
B&O item 1, B&O item 2, B&O item 3,...................B&O item 735
Beovirus? What's that?