Yes, it is a tall screw looking thing behind the lever for the "STOP" button....its a flathead screw, long tube, with a locknut at the bottom (14mm I believe...) Counterclockwise is slower, clockwise is faster.
The SD does not have a knob on the dash, they don't usually need an idle adjustment when its cold....they have enough cylinders to keep going.
However, it should be set to about 700-750rpm, not 1000. Are you sure its idling too high? Sometimes the tachometers just read wrong. For reference yours should be running about 3100rpm at 70mph on the freeway......
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