Thanks for the suggestions!

First, I took out the cruise control amplifier. Would the lack of the amp produce the surgeing idle and stalling problem?

Secondly, I cleaned the throttle body and the large flap under the air filter with carb cleaner. I also removed he hoses from the idle control valve, removed the ICV, and cleaned that with the carb cleaner.

The result was that the car performed beautifully for about 2-3 days and then the surging idle and stalling problem returned.

Nick