yo,
As Ron said;
C6 Shift Indicator Adjustment; "...There's a thin cable going from the shifter to the shift indicator. Once you take off the steering column cover, you'll see the small cable and the shift indicator component. The positioning is adjustable, just have to unscrew it and move it around till you get what you want..."
Source: by Dustin S (Dustball, Mellow Yellow, Mr. Laser Boy)
& Shift Indicator Cable Repair in an 84; "...The plastic tubing that holds the gear indicator cable is broken in several places, starting at the point where it meets the indicator housing, which removes from the rest of the cluster with two screws. I ended up removing the cable entirely (which was broken as well) and replacing it with a thin piece of wire (from a CAT5 cable, actually) that is flexible but rigid enough to not bind. I still need to find a thin enough piece of plastic line to house it before I can reattach it to the shift arm, though..."
Source: by jkorbes