I still don't know why you have P0100 style codes that is for OBDII and you got a 95 with OBDI unless something was changed on you truck. As well as the transmission temp sensor was a Ram only thing pre 96. Dakotas didn't come with the sensor.

Since your IAC code keeps coming up, yes it could be the IAC or just bad wiring. Test each wire for correct continuity to the PCM.