After few drying days, I applied a coat of Klir/Future.
Then, a dark gray wash in the panel lines.

before wiping


I then applied the decals.
To give them a worn look, well I.... damaged them ! with a sand pencil and sand papers.

After this torture session, I was not sure that decals will stick well, so I've brushed them with Klir. Then with the airbrush.
Next comes a coat of satin varnish to give me the work surface for the weathering to come.