Hah! Thanks for the pointer.
I did get my hands on a reamer, the rough country branded one. (It was the one that shipped fastest.)
I've also learned that a pitman arm is useful if your goal is to break pitman arm pullers. The harbor freight puller I started with just deformed its screw. The Lisle "heavy duty ford" one snapped right off. And I don't have a welder where I currently am.
I'm now waiting for one of the cone shaped pullers to come in the mail.
The second option is to remove or at least loosen then steering gear box and pivot it up so that I can ream the arm while it's on the van. I'd like to at least have a spare arm handy before I try that, so I think I'll wait for that to show up at the same time as the third puller. That would also give me the option of cutting the old arm off.
The third option is to just order a steering box, since I'm pretty sure I'm due for one as well, but then I have to tackle the question of which one to get. There are a couple of all new ones out there now, which may or may not actually be the same ones. I wonder if anyone has any experience with them. Hmm, that might be another thread.
Finally, the frame cross member on my van has been cut some with a torch under the steering box. Which as much as it's handy for this work, I'm not sure I understand why yet. I wonder if they meant to swap the arm, but couldn't get it off and then just welded the drag link. Edit: It looks like they just cut out the OEM drag link mount before relocating it.