Thanks Bertl, Nigel and RAGIII.
I had left the upper wing still on the sprues because after cleaning up the sprue gates the edges have to be painted blue anyway. Normally, of course, I separate the wings from the sprues before painting.
As I am a comfortable and lazy modeller, I bought the painting masks from CSM. This makes painting the taped edges much easier and saves time. There are also masks for the cockades included, so if you want you can paint the French cockades yourself.

Cheers
Joerg