Actually, I do not know what body car you have. All the locks can be removed without removing the door panel except some models cannot be removed without turning the key, which you will not be able to do, obviously. Here the inner latch may also need to be remove so the two loose pieces can be twisted far enough.
The later cars have removable lock cylinder assemblies that can be removed without removing the handle. I do not do too much of that kind of work so I don't know the exact procedures for all models. As to the seat switches, the knobs pull off and then there is a small screw that allows the plate to come off. Here again it could depend on the model.
Bosch Master, ASE Master, L1
33 years MB technician