i recently bought a 1978 3/4 ton 4wd pick up.
i am trying to find out how to adjust the steering box...
Before i go and replace it...
I have a lot of play in the stering wheel...
kmink@shoshonebannocktribes.com

it probably needs rebuilt if it has a lot of play in it. make sure its not the other stuff though first, like loose/worn linkages. Im restoring a 73, so its essentially the same as yours, and i have to replace my power steering box. it was remarkable what the tie rod ends do though in the way of tightening it all up... now if i could just get an engine and put it on the street lol

There is a lock nut on top of the steering box. Loosen it and then you can tighten up the center shaft with a screwdriver. This is the worm gear preload. Too tight and it will burn up, but too loose means sloppy steering. If you are already leaning toward replace the box, then you have nothing to loose.