I just wanted to say a big thanks for all the useful information and thread /site leads on here. Thanks to you lot, hubby has just replaced said 'o rings, in the rough time stated (3.5 hours) with the help of a good mate. If anyone is going to do it, the guides and tips on here are a great help. Ideally a two man job as it's all a bit fiddly, but hey what a success! He found a few things that aren't listed on any of the threads we found, so if anyone in turn needs any help, he'd be happy to reciprocate. Thanks again for this great forum.