Just a follow-up:
I bought a new cable (and rubber sleeve) from the dealership for $40, and installed it a couple days ago. Very easy job. Ended with an "Ohhhhh so that's how this thing is supposed to work" moment. My old cable was seized, plus the lock ring on the dash was loose, so when you turned the knob, the whole tumbler turned. It was also quite gumbed up at the throttle end of it, and the inner cable had pulled loose from the tumbler on the dash. Now that I've put the new one in and observed how it functions, I can see why the old one wasn't working out. A very cool feature to suddenly have on my car.
So it starts now and stays running, quite smooth. The bad news is, it vibrates like mad, the whole car. I just changed the motor mounts so that's not the issue, although the trans mount may be bad. Just to make matters worse I decided to tighten up the motor mount bolts, and snapped one in half. That's a whole nother thread though.When I get that fixed I'll play around with the vibration issue ... it's not unlivable.
But, the idle control cable made a HUGE difference. Between that and the fast-glow kit I installed, this is like a whole new car. A new old car, that is.

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