Does anyone know what the factory position for the throttle stop screw is? I know it doesn't specifically have a reading, but is their a way to set it back to stock by determining its length perhaps ? ( It was modified before I owned the car, previous owner thought this was how you determined idle)

 

Article on how to adjust it here. It's essentially a minimum idle speed screw and you set it to the specified rpm, I dont think you could really use how far it's screwed in as a good gauge.
http://dev1.remote-app.com/techartidle.html

 

Awesome, that is exactly what i was looking for. Thank you.