Just me here. I over coat with Testors (MM) clear lacquer gloss. I use a product here in the States called "Mona Lisa Odorless Paint Thinner" It is very well known for how weak it is. Mix's well with my brand of oil paints but will not attack the clear coats. After washes I cover with a flat coat then weather.
I will agree with Erik, don't get use to it, on this one. It'll be like enlarging anything without the proper amount on pixelation, if there is such a word.