There should be no play in the gear box. Look here for how to rebuild and adjust
http://chevy.oldcarmanualproject.com/booklets/5220mts01.htm. The procedures are the same no matter what year you have. Adjust the box, then work your way out to the wheels checking for movement. When the steering wheel moves, so should the tires. Have the tires on the ground, full weight on them, when checking for movement. Tie-rods and drag-link have adjustable ends. Replacement tie-rods come in sealed, modern type joints, or replacement stock type. Mine drives better with the newer type joints. With a fully adjusted steering system and non-worn spring bushings, it should drive like any other truck on the road. Tires will be the next thing to address. GM didn't sell crappy driving trucks.
