On my Rotary two post lift the arms have a short and long flip up lifting pad which covers most needs but on early cars with the tall running board splash aprons we had to make up taller pads to reach the frame. Our model has a pivot pin on the pad that runs through the arm and is held in place with a snap ring. IIRC the pin has about a 7/8 diameter so we just welded that size pin to a steel box that drops into the factory hole in the arm. We often have to jack up with a floor jack to get the taller stands under the running boards and again to get them off but it is safe.
