I'll get some more photos this afternoon, but here's the top part of the headset after cleaning. I didn't get a before photo, unfortunately, but I had to show y'all how well this came out.
The bottom bracket was the same. Once I got the grime and old grease cleaned up, the internal works are in nearly pristine condition. I'm thinking that this old fella didn't see much use in its day, because there is virtually no wear on any of the bearings or cones. Still working on the wheels, but they're also cleaning up nicely.