With apologies to the OP:
Neilrr: Facelift time was 97/98. You'll see some R plate facelifts and some S pre-facelifts. Depended on stock levels at the time, I suppose.
As regards what was changed: Quite a lot I think. At least: Bumpers/bootlid/rear lights/front door airbags fitted. From my (bitter) experience the following have also changed: front seat belts, ignition switch, door panel grab handle mounting points( meaning you can't (easily) put pre-facelift door cards into a facelift, even if you did ignore the airbag), electric window motors, central locking electrical function( the vacuum pumps/motors/hardware in the doors are the same but the control side is different), the doors control circuits ( facelift cars have a "door controller" in the front doors where items such as the mirror,window,airbag,etc are all controlled from.) and probably a host of other items that I haven't had to fiddle with yet!
Andy