Do as Kevin suggests, have someone move the steering wheel back and forth ( just a little ) so the steering gear takes out all the slop each way. If the tie-rod ends are loose, you will see the rod move before the steering arm does, there should be no free movement at either end.
Go to the steering box, have the driver slowly move the steering wheel with one or two fingers back and forth, if the wheel moves before the idler arm does, the adjustment is off at the straight ahead position. I would not assume the gear box is right.
https://chevy.oldcarmanualproject.com/booklets/52mts20/index.htm This manual will explain the adjusting procedure. You will have some free travel at the ends of travel in the gear box, so all checks are made in the straight ahead position.
A correct steering system should have about 5 minutes of light pressure movement each side of straight head in the steering wheel, ( using a clock face as a gauge for movement ). At the same time, if the steering wheel moves, the pitman shaft should also be moving.
Another thing to check is the straight ahead adjustment. You will need to unhook the drag from the pitman arm. Slowly turn the steering gear fully to the left, then count turns fully to the right.
Don't force it once it hits the end of travel, go easy! Turn back half the amount to dead center. It should have tight spot dead center. If you don't feel the tighter spot, or it's not in the center, the gear box is assembled wrong or not adjusted properly. Don't go by the steering wheel for center, if necessary, pull the wheel and install in the correct location if it's off center. This center adjustment can make for a loose driving truck.
Just to be clear, there two types of tie-rod ends and drag-in ends, adjustable and non-adjustable. The non-adjustable are a sealed type ball and socket, adjustable have cups, springs, and ball studs. To adjust this type, the end screw plug is tighten as tight as it will go till it bottoms out, then backed off to the first cotter pin hole. Be sure to grease all the joints.
As a side note on this type of joint, the ball studs can become worn to an egg shape, this creates a hard steering because the cups and springs are always moving in and out around the egg shaped ball. With a true round ball end, the cups and springs apply a steady pressure. If you replaced the cups and or ball ends, you may find as I did, the cups don't fit the ball. I spun the ball end in a drill press and used lapping compound to seat the cups to the ball. Mine was terrible to drive till took it back apart and lapped everything to fit.
