Use these on a Mini when using longer bottom arms to get negative camber. You don't want to run out of threads!
To check for wear, just jack up your car and grab the wheel on either side as if to attempt to steer the car. If the wheel rocks in and out as you attempt to make small quick steering direction changes, the rod ends are probably bad. If you look at the back of the wheel while a friend does this rocking motion you can typically see the bad rod end in action. These tie rods fit racks with 7/16" UNF threads which includes MG Midgets after 1972.