The window frames for estate, saloon, and coupe are all of the same structure design - back of the front door on B post here are couple of self tappers to remove. the frame shape olong the top archs over the window rubber gripping it - along the bottom edge there is a metal blade which pushes into ta grove in the window rubber. As Dave says youneed to tease this out of the slot 1st - I have managed to remove the frame without removinf the rubber and glass - not done the other bit - like put it back
looks like it might be a one way trip without removing the glass and putting it back all in one go. Looks like I am going to find out on my green estate soon as I noticed that the trim (shiny bit)has had something drop on it which has bent it out revealing a load of tin worm attacking the frame - anyone got a spare o/s frame - sods law - I sold my spare pair 18 months ago