I was able to secure a timing light and engine analyzer (thanks to Chris), and found that the timing was advanced by about 10 degrees from what the label on the hood indicated. After correcting this, she runs much better, although I am still fighting the plethora of vacuum leaks under the hood... I know I'll have to recheck the timing once I have replaced all of the vacuum hoses, the intake manifold and exhaust manifold gaskets, and anything else that might be leaking under there (Eris knows what that might be, but she's not telling).
I am also going to re-rebuild the carburetor; this time, instead of using spray carb cleaner and a brush, I am going to do what I should have done in the first place: a nice long soak in ChemDip. I have also ordered a kit to replace the idle jets with larger ones to prevent clogging. I could have drilled them out to .032" but it's not an easy task to find a drill bit in that size - they don't carry those at the local hardware outlet :)
The other decision I need to make is whether to order a new electric choke kit or replace it with an old-school manual choke... the biggest benefit to the manual choke is that it would be a de facto theft deterrent, since there are not that many people left who even know what a manual choke is, much less how to operate one; the would-be joyrider would probably flood the carburetor and kill the battery trying to get the Jeep started :) (Okay, yes, I am old and cynical - deal with it).
The goal of all this is the coveted inspection sticker - the county we live in performs emissions testing and Randi is one year shy of being exempt, so I need to get everything lined out before I go to the station. Of course, a clean-running engine is good for everyone, but the Byzantine twentieth-century emissions plumbing is very prone to any number of failures that leave the engine polluting more than if the emissions system weren't there at all... I have confidence that it can be done, however. Even if I have to replace every last component. Sigh.