Thanks for the video link, you made my day. I have just completed my Dec service during which I replaced all the bearings with new.
I had just two problems the first was down to a bit of corrosion on the shaft. The bearing between the red washer and the body of the mount came out with the shaft and proved difficult to budge so I ended up spraying a bit of D40 on the shaft and eventually the bearing released.
The second problem I encountered was with the button on the Dec clutch, it didn't go back in square and I had to dismantle everything to push it through and start again. The second time I pushed the button in from the back before attaching the worm gear.
Otherwise a long overdue service, tomorrow I will try the RA axis.