[Doc Watson]

The internals were then exposed and show how the dip switch works. Also note the mirror glass is wedge shaped. The 'ball' is located between two plates and you can see the 4 tabs that hold the top plate around the ball. These would need to be bent back to allow removal of the ball. The ball/socket assembly sits on two springs (the rusty bits) and is held in place by a curved wire. To remove this you need to press down on one end of the socket assembly and you can then remove one side followed by the other. This releases the ball/socket assembly from the case but as mine still has the original stem (not for a GT40!!!) I cannot remove the assembly. The last picture shows a close up of the ball and stem. It looks like the ball is screwed into the stem, maybe brazed or soldered?? this will be cut off at that joint so the socket plates can be removed. All that is then required is to pull up the tabs for the plate and a new ball can be replaced. I'm waiting for delivery of my new ball and stem and will replace it then.

Hope this helps

Andy