Similar treatment has been given to the other side, and you might just be able to see where the same pigment has been applied to the cab end.
I thought that the shine from the oily finish under the running plate was a bit too bright, so it has been dulled down a little with some dark brown pigment. This was applied in small quantities (heard that before?) with a soft brush.
I think I'll finish this subject right here. Resist the temptation to fiddle!