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And even then, if your tracks are within 2"of a long fall, you should seriously consider erecting a barrier of some kind at the edge, either clear plexiglass, or a robust fence meant to look like it surrounds a field, maybe a hedgrow...even add a healthy half-berm of dirt...anything against which a tumbling and expensive car or engine can come safely to rest.

Or, you can do what many of us do...wait until after your first incident.

-Crandell