I just finished assembling a proto 2000 8,000 gal riveted tank car. Now I'm wondering about weathering. I think this is a gasoline car so there wouldn't be any dark oil stains on it. I think some light streaking down the sides and a bit heavier on the dome but I'm not sure. Also the car has a built date of 1920 and I'm modeling the fifties. Maybe the weathering would be heavier? Anyone have any ideas?