Engine was fully warmed up.

I got some new M5 x 30mm screws for the TPS that don't have such a large cap on them, and was able to get the TPS "adjusted" down to 1.01 volts at idle. That's as good as it gets without drilling out the sleeves for more adjustment. I think that should be well within the middle of the spec range now.

I have the 2G alternator. At current "fast" idle, I'm getting 12.88 volts at the battery posts with the headlights on and the blower motor running. With those off I get about 14.1 volts at the battery posts. If I unplug the IAC and let it idle around 500, I get 12.49 volts at the battery posts with everything on, and 13.27 with the lights and blower off.

The accessories on voltage seems a little low.... but I would expect if the computer was idling up to charge better, it would cease as soon as I turn the lights and blower off. It never changes

I'm going to look at what the IAT sensor is putting out next, I didn't realize the computer used that to determine idle..... Like I said in the original post, I put a new ECT in without change... but that doesn't discount a wiring problem between it at the PCM.

My Ford Fuel Injection book showed up today too, so I'll do some reading and see what it says about idle speed.