https://www.youtube.com/watch?v=3Xc7r0djEKo
https://www.youtube.com/watch?v=zju4nagtiCU
here are two videos part one and two of Les Andrews with pictures explaining the situation. I too found the Nu Rex tool was getting me in the ballpark, but when I manually did it with a test light as described here in the video and better so in his book, I had a better run. remember in the book it talks about CW and CCW ...pay attention...clockwise and counterclockwise!! I found his red book pretty easy to follow but you need a voltage light...