(1) Idle Air Control (IAC) for the Holley harness is a 4 wire stepper type (A Lo, A Hi, B Lo, B Hi). The Edelbrock hardware is a PWM (pulse width modulated) with only 2 wires. How do I wire the Holley harness to the Edelbrock IAC? I called Edelbrock and they said the keyed side of their IAC connection is the "A" side. Do I just for get the "B" side and that's it? (see picture)
The Edelbrock throttle body can be ordered with either a 4-pin stepper Idle Air Control valve, or a 2-pin PWM IAC. Apparently, you have the Hitachi linear PWM 2-wire IAC. A stepper IAC and a PWM IAC operate totally differently. It appears the Holley HP would use a PWM output for the IAC, and Edelbrock indicates the IAC is powered with 12V and signaled with a PWM grounding pulse. See note on image below.
(2) TPS: at the connector I need help identifying what color wires do what on the Holley harness for their throttle position sensor (TPS). The instructions only mention what pin each wire goes to at the ECU. When I looked at the pins at the ECU, the wire colors don't match the TPS connector wire colors. Maybe I don't know how to count pin connectors.
Get a magnifying glass, as the pin numbers can be VERY small, as you can see with the letters next to the pins in your first photo. Also, they are usually only numbered by the row ends. So, you may find a tiny "1" at one end a a row of pins, and maybe "11" at the other end.
The Edelbrock TPS is wired as in the image below, and I added the Holley pin-outs to that. You can see on your Holley wiring schematic the GRN wire is the Holley TPS signal wire, with BLK/WHT sensor ground, and ORG has +5V sensor power.
I do not know the spce's of teh Edelbrock PWM IAC. You should call them to verify the amps it uses. It is a solenoid 'coil' device, and must be under 2 amps or you will need a power transistor to handle the load between the ECM and the IAC. Holley sells those of course, or you can do your own.
Holley or Edelbrock may have swap connectors for either device if you do not want to make or splice your own. Hope that helps.
Look at the specs for the Edelbrock stuff, and where it goes on the Holley stuff. Connect the dots
. This is your wiring, so verify everything yourself :