I have all kind of pictures of cars with different combinations from contemporary magazine tests, brochures and later images. There are Black wheels with black shifter knobs both AT and MT, ivory wheels with black knob and ivory knobs for both transmissions and even one of a black wheel with ivory knob. I think this is one of these questions that can be answered only by those who bought their car new and still own it, or someone at MB who is able and willing to share this info. One thing I can say, though, is that all 190SL pictures I have seen of cars with ivory wheels have ivory shifter knob. Maybe it is a cosmetic feature that owners adapted from the 190SL and not a MB feature.
The pad on the steering wheel, however, I think was always an ivory shade matching the wheel, not the interior