My layout is not on level ground, and Ive done so much as to lift legs 6" to level it out, and its still not perfectly level. In the yard is the main spot. I pride myself in maintaining a good freight car fleet, which means they have a tendency to attemt to make the soutbound departure trip on their own. Any suggestions as to how I can stop that from happining. I have been sticking nails in the ground at the end of trains, but I think there might be a chance for more realistic operation. I know railroads use wheel stops on spurs, and Ive even gone so far as to think about how I could design a operating brake wheel. Any ideas before I just level it out?