Door trim has to be removed, also you will need access into the door panel through the plastic damp proof sheet, to remove the electrical connectors. You may need some duct tape to seal. Take your time in removing as there are cables in the door panel. Not sure if the speaker comes away with the panel or not!
Not a big job, approx 30 minutes. The door closing handle is fixed at the top with a screw, there is just the odd screw with a plastic dome. The fiddly bit is feeding the door opening catch through the trim when you come to re-asemble. Don't forget to connect the door speaker again if you had to disconnect it.
best regards, Rustic