Easy job of the day was swapping out the sidelight holders. The old perished ones have been consigned to the bin. The new ones hold the wee bulb a lot better.
The slightly more difficult job was to remove the driveshaft to measure it. 12 bolts later and I have it in my hand. I took a couple of measurements and replaced it.
Only after did I realise that I should have recorded quite a few more dimensions to define it better. I have contacted an engineering company to see what measurements to take.
It's also puzzling that their driveshafts have only outer circlips on the CVs. 
The ones I have at the moment have inner and outer circlips. Hmmm.