Nobody answered so I am answering my own question. Yeah, I'm like that. The short answer is "yes." Take out the bolts holding the shaft ends, pull the shaft, (in my case I wanted to take out the body lift, so had to jack up the cab; my easiest option was to simply jack the cab, thereby jacking the main shaft out of the yoke). My steering shaft was pretty nice yet, (Montana truck, no rust, but many are just big masses of rust, and most likely should just be replaced). Put the shaft in a vise and start hammering. Keep the shaft on the most solid footing you have, and don't break it. Inside are: a split plastic shim that goes all the way around the inner shaft, a thin steel leaf spring, a rubber/plastic bushing between the two shafts, (at the end of the bigger shaft, easily visible before removal), and a rubber plug at the upper end to keep out dirt.
The bushings and shim keep the inner shaft tight; it's a very sloppy fit otherwise. Lube it up good, put it back together. I telescoped mine all the way in and out to make sure it would go closed enough to lower the body. Even lubed it was still a fairly tight fit, but much easier than the original separation. On mine, after reinstalling, the small shaft can telescope inside the larger one about two more inches before bottoming out.
During reassemly the bearing at the steering shaft column end kept coming out of place. There is only a rubber sheath around the outside of the bearing, and a rubber base between bearing and shaft to keep it in place. I finally had to put a hose clamp on the shaft behind the bearing to keep it in place. I think the manufacturer should have put in a c-clip to hold the bearing in place. Check the main through-the-firewall shaft for play before putting the intermediate shaft back on. If it's sloppy, the bearing has gotten pushed up out of the plastic steering column cap.