By default it is not included in the build, you must #define GHOSTSCOPING in the torqueConfig.h to enable it.
The distance can be set via the mission file by adding
visibleGhostDistance = "1000";
Or if it is not set in the mission file it will default to what is defined in torqueConfig.h #defined as GHOSTSCOPING_DEFAULT_DISTANCE_IF_NOT_IN_MISSION
The mission default distance can be overridden on a per connection basis by using gameconnection:setVisibleGhostDistance and gameconnection:getVisibleGhostDistance
The logic for setting the scoping distance was moved from shapebase in the original design to SceneObject so that it will affect cameras, players, etc.