Hello, I have a na 6.5 and 4l80e in a 85 c10. The power train didn't come with the pcm so I got the atomic tcm. My issue is it requires a tach signal. It has the engine speed sensor on the back of the engine but I can't find any information that explains how it's wired and if I can use it for the tcm. Any info or easier ways to do this would be greatly appreciated.