I finished mounting the shoulder hubs. I will update later with pictures. I attached the magnets together with some wax paper between them. I them applied some JB Weld to the new magnet and put the shoulder hub into the leg. After a while I pulled the hub out and separated the magnets. I then put the magnets back into position with another magnets, on the other side of the leg, holding them in place and squeezed towards the leg wall.