Swings and roundabouts K. To provide tracking adjustment you need a left hand thread one end and right hand the other. At least with the Morgan setup, and whatever other vehicles the design was borrowed from, the steering rod is cheap to manufacture with rod ends simply requiring male threads cut directly. The Classic Mini system Jon refers to have male threads on ball joints requiring steering rod to have matching female likely via some sort of coupler or oversize tapped tube with split and clamp as on my Land Rover.
