got it done - very fiddly job. Not sure if I did it right but it worked and everyone went back together fine. if anyone else interested; 1. remove triangle plastic cover from inside rear of window by prising it towards front of car. 2. remove the two torx screws holding the cover that fits over the inside door handle. 3. once this is prised off there is another torx screw to remove which fixes the plastic decorative door panel to the door. 4. the door panel should then prise away from a whole series of press studs that hold it in place. 5. there were two electric connectors to separate just inside the handle mounting to remove the panel completely. 6. there is then another smaller metal panel to remove. i firstly removed all the hex head bolts from around the edges using a 10 mm socket. I think there were around 12 of these. 7. at this point the door panel came away enough but I couldn't see how to get it to come completely off. there is some kind of connecting bracket to towards the rear of the panel that I could see but not access. There is another hex head bolt that goes through the door further back and I wondered if this was the final fix but wasn't confident to remove this one in case it was for something else. 8. anyway it didn't matter as with the window up and the door panel loose enough to pull slightly away and down, it is possible with a long socket extension to access the 8mm hex head bolts that hold the handle in place from the inside. 9. this part was fiddly. there are two bolts toward the front and one towards the back. there was also some tape to remove over one of the access holes. 10. There is also the pull cable to remove. this unsnaps from a slot and then the ball end of the cable can be twisted to come out of its retainer. its hard to see but you can see how it attaches by looking at new handle. i also got my son to shine a light behind the door panel but its a bit awkward to have someone else there as there is not a lot of room. if you trace this cable it will help to undo other end to give some slack to play with. at other end, there is a little black to unclip to get to cable ends and the end just prises out. 11. new handle fits by sliding back portion into door first and then rotating front. 12. fit the ball end of pull cable first and then pull cable back to snap it into position. 13. refit everything in reverse and should be fine. hope that helps someone else who might be looking to do this.
