I am putting the car together again after freeing the clutch release shaft. I noticed one of the gaiters had a split so decided to replace them both. Now there is a small hole in one end of the gaiter and it has to fit over a much larger diameter so I made the following tapered plug to help. It is made from a piece of 18mm diameter steel turned down to 12 mm at one end and a taper at the other. As you can see in the next photo it works a treat. Remove the ball joint and slip the former into the end and the gaiter slides up the taper and onto the arm. Just thought I would mention it in case you need to replace a gaiter and know of someone with a lathe.