How do you adjust the transmission cable on a Chevy G20 1991 van?

To adjust the transmission cable on a 1991 Chevy G20 van, first, locate the cable linkage on the transmission. Loosen the adjustment nut and pull the cable to achieve the desired tension. Ensure the throttle is fully closed, then tighten the adjustment nut while holding the cable in place. Finally, test the gear selection to confirm proper adjustment.