The dots on the speedo show the safe speed ranges for each gear (up to the first dot for 1st gear and so on).
The bowden cable is easy to adjust, it is located under the air cleaner above the oil filter.
Do a search and you should find plenty of posts on how to adjust it.
My car is a '92 model, but was made late '91, when they switched to the 1st gear start.

__________________
1993 320TE M104
---------------------------------------------------
past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
----------------------------------------------
"music and women I cannot but give way to, whatever my business" -Pepys