Gentlemen
Success, after seeing pic from Low Rider as you say easy to remove, had to ease old gaiter off plastic where it was stuck on, cleaned it up and stretched the new one over and push back into position tucking the new one in as elasticated. Job done, but it does not look as tidy as the old one but it will bed in with use. A BIG thank you to one and all.
Re coding my remote (brick) purchased on Ebay on Monday (another post)