Hey fellas,
Ran out of time tonight to troubleshoot, but wanting to get suggestions,
I turn the key and everything lights up, fuel pump kicks on, but the engine won't turn over? I'M thinking that it's either a bad starter connection, or my ECM power wire is not getting the power. VATS???
Anyone, anyone?

I dont know how you have things setup, but if you have a modern instrument cluster, the CEL will come on if you have power to the ECU.

VATS could very well be killing you. It sure did with mine when I went standalone.

Doesnt look like a VATS problem to me. If it was, the engine would still start and shut off after 1-2 seconds. If the engine doesnt even turn over, it is definately your starter connections. Make sure you get +12V to your starter when your key is on the IGN position.

Are you going manual transmission? Maybe bad clutch switch...

Mine sometimes doesnt start becuase it doesnt think the clutch is depressed

3rd gen VATS or LS3 VATS? 3rd gen interrupts the starter signal.

LSx VATS kills then engine after a second or two after it started. As already stated, the clutch switch would be a good place to look if youre using a stick.

GOT IT RUNNING!!! Was definitely the nuetral switch,
Now just need to lean it up. Seems to be running rich. I'm thinking it's cause it's got open headers right now, and the O2 sensors are probably not reading very accurately.

Mine doesnt run for a damn with open headers either

The car is scheduled to get the exhaust done next thursday.
dual 3" X-Pipe, and bullet style mufflers, dumped before rear axle.
Hope this helps out, if not..... i guess a new tune is in store!!!