Well I would think it work okay based upon my knowledge that some 240D's had manual windows, although the one I owned did not. The 123 door sheet metal should already have the holes needed, however, you would need to make a hole in the trim panel.
If you seldom have company riding with you, it might be novel to do the conversion on the drivers window only. That way you have the best of both worlds, remotes for the unreachable windows and manual for yours.
