Ahah!
I did not replace the IAC.
I found, on these forums and another, directions for resetting the "minimum idle speed" on these TBIs. I did not find this info in my Chiltons manual.
First you have to drill out the plug covering the screw on the front of the TB unit. I didn't have to remove it from the engine to do so. Instructions are to turn on key, cross A and B pins of the ALDL then unplug the IAC. Start engine then adjust the idle speed screw to around 400 rpm or so. Turn off the engine and plug the IAC back in and restart. A relearn drive fine tunes the idle control.
Mine would not even idle, period, with the IAC unplugged. I had to turn the screw in 3 turns just to get a slow idle then almost a 4th full turn to get to what I feel is around 400 rpm and I stopped there. I have no tach but my earometer feels it's close.
Once IAC is plugged back in the idle speed comes up more. I drove it all around town for an hour or so and it never once died at a stop as it did before.
That's just one drive but it feels promising.