I am not familiar with stripping the Webley Tempest/Typhoon/Hurricane series, but I believe it is quite simple and actually Webley used to sell them with information on how to do this.
I suggest you post a question on the General section, asking for advice on stripping and reassembling your pistol, and then follow the advice in the tuning guide. Someone is sure to send you a copy of the stripping manual.
The pistol you have is now a collector's item as they are no longer made, and also they are very nice to shoot so they are worth keeping in good order.
Have fun!
This thread covers most of the strip...
http://www.airgunbbs.com/forums/show....php?p=2416711