Hi Chris
My 96 +8's doors used to squeak, I tried several things to stop it but no success, then I noticed that NeilM's Roadster had a small rubber seal that runs around the inside edge of the doors where it shuts against the body, my car did not. I am not sure when the factory started fitting them as standard, maybe your car does not have them? I purchased these from a main dealer, they were only about £4. They were easy to fit with a sticky backing and the squeaking stopped. Also stops the bottom door edge rubbing the paint.
Hope this helps.
