Hello everyone. I am new to mercedes, but interested. I am thinking of buying a 1982 sd. I am concerned about 2 issues. The speedometer only goes to 80 mph, and the shifter labels say 12d. On other sd models the speedo goes to 120 or so and the shifter labels are 23d. Is this the same transmition and why the differance in speedometers? Thanks for any help.