Guru Nick Says...
"Nothing like when I was stuck on a crippled Merchant Vessel in the middle of the Indian Ocean"...

:
But then most engineering fixes are not THAT difficult....
OK, I have homework set. 1. Remove wiper assembly. 2. Take whole lot to engineering merchants in middle of Barnsley (M C Mills). 3. Look daft, appeal for sympathy and someone with knowledge and 4. Buy bits or retreat with tips on where next to try.
Slightly sadly, will SORN magnificent beast on Sunday... Expected to do work in winter but not just yet.
Next week for that, will keep you all posted...
Robert