The adjustments are at the transmission, but the aligning sleeve and pin will be at the top of the column inside the engine compartment right at the shift arms.
1. First make sure the brake is set AND a wheel is chocked just in case.
2. First step is an inspection to make sure the bushings are intact and the rods are tight in the arms still.
3. Then get under and disconnect the rods from the transmission arms. Does not matter at this point if you're in neutral or not, because you'll be able to manually do it after.
4. Maneuver both shift arms to their center positions so the trans is in neutral.
5. Back up top, put the shift lever in the cab into it's neutral position too. This just gets you close enough to do the next step.
6. As ngsd mentioned, there is a sleeve welded to the top of the column that, when the two shift arms are in neutral, will line up with two holes in the arms.
7. With the holes aligned with the sleeve, insert an appropriate size drill bit. What, 3/32" maybe? I forget, but there is a "correct" size. Probably some leeway though.
8. With all three bits aligned, go back down under and re-insert the shift rod adjuster pins into their appropriate holes in the shift arms on the transmission. Adjust if necessary.
Do not move the arms here. Instead, if they don't go in easy and naturally, thread the adjusters in or out to line up with the hole.
9. Clip them back on, go up and remove the drill bit, then row the shift lever on the column through it's paces to see if things have improved.
Usually they do, so hopefully no further steps are needed!
Paul