I drilled/knocked out the epoxy on one I was trying to fix, and there was an allen screw inside. I used my Scangauge to set the idle TPS percentage to factory specs. I would try what 'iminhell' suggested first it works too, especially if you don't have any way to look at the TPS readings.
EAP with 1/3 of the cold weather package. No block heater or TCS.