Run the adjuster in (clockwise) about 2/3 to one complete turn.
Another possible adjusment is "when" it shifts. If it is shifting late and you are letting up on the gas during the slushy shifts then you can adjust the vertical link from the throttle linkage to the proportioning valve at the back of the pump. Making the link shorter will make the shift earlier.
The concept of these two adjustments (and at least one more that I won't get into) is to make your third shift harder without making the first shift unbearable.
Bosch Master, ASE Master, L1
33 years MB technician