The outer scrapers can be removed quite easily. With a suitable plastic trim removal tool, just lever them upwards starting at one end, taking care not to bend them. I can't remember if you need to remove the mirror as well, but that's just a case of unclipping the inner trim with the tweeter on to access the fixing screws. You may need another pair of hands to hold it, as you can't remove the mirror completely without removing the door card and unplugging the wire.
Re-fitting is just a case of tapping it back into place. I used a cloth and a nylon headed hammer when I last did one.