Very rough idea of what to do from my poor memory:
You removed the steering column and steering box which means you pulled the pitman arm off, removed all the parts on the steering column, jacked the truck up and pulled the steering box and column from the bottom (or did you lift up the cab)? Just reverse the order.
Once you get the steering box and column back in place, you can start with the shifter/selector (it fits in one place and has screws holes to mount) and then the shift rod with lever. Be extra careful with that plastic dial, indicator and bezel when you install. They break real easy and there very difficult to find. I would install the steering wheel loosely (in case you have to remove it again).
Verify that the Pitman arm only goes on in one position on the gearbox shaft. Hook up you drag link. Should be in the shop manual.
The next hurdle is connecting the shift selector arms, linkages and shift arms on the transmission to the correct position. The is where you need the book and setting gauges. You will also need to set/recheck the throttle linkage to the HM. Again you need the book. This gets you in the ballpark until you are able to drive the truck.
Last edited by buoymaker; 06/05/2021 9:45 PM.