I read the documentation on how to do it (many thanks), and got to the point of actually removing two screws to release the chassis, then stopped and thought long and hard about what I was about to undertake. The thought process was along these lines:

a) Assuming that the hard drive really is faulty - and it seems odds-on that it is - do I want to go to the time and expense of procuring a new one and re-installing the OS and (should the diskettes be faulty) procuring a new copy of said OS?

B) What are the chances of me completely messing up and being left with just a box of spare parts? (quite high!)

c) Assuming that an enthusiast becomes the new owner, how easy would it be for them to resolve the problems? (very easy!)

So, sad to relate, I have chickened out and but her back together again, and will now take photos etc and put her on sale.

But I really do appreciate all the enthusiastic help, encouragement and advice that you have given me in this forum .

ciao

johnboy