After the French folks paint the top of the train white...

Or just shoveling mud on it might even do it. If you don't have paint handy that is. I wonder if you could tie down tarps to cover.

Just finished watching again. You are so right about black paint! It was only taking a few minutes to put on the white. Black would go on just as quickly (well, I suppose they'd have to let the white dry awhile.)