Thanks for the heads up about the Allen screw under the barrel, I would never have thought about there being one there. It certainly made life simpler and the cylinder came out with no problem at all.
I have baulked at taking the hammer and trigger apart at the moment as there's not a problem with it but at a later date may do it out of curiosity.
Anyway I can now refinish the stock, so thank you.
Just an aside how did you know there's a valve release screw under the barrel as there's nothing on the internet about stripping these?..dom