Couple more pics....
Heres something you don't want to see on the side of the road - fortunately it happened in my workshop!
On the plus side one of the brushes in the starter motor was just stuck in the guides and didn't need much to get it moving again.
Just a few footnotes:-
Removing the starter is fairly straightforward. There are 2 bolts and one 12v connector. Once those are off you need to release the sealed end from the housing. Its a bit tight and I used a piece of wood and tapped it with a hammer. If you can get a good grip on it you may be abel to pull it out. Is there a better method for this?
Watch out for the oil cooler pipe - if its rusty then its going to be fragile. I loosened the radiator which would have put a strain on the pipe so that was probably the straw the broke the preverbial camels back. Its rusty anyway so better happen in the workshop!
Also found a handy workshop guide online. Whatever you do don't pay for one!
cheers and thanks for your help.