I originally had the whole thing mounted down lower on the firewall for a cleaner look, but when I was moving things in the engine bay I touched this and the engine immediate turned off.

Ive had idle issues with it jumping up and down, so could this be the culprit? Where would it connect to? I barely move it and the engine drops in revs. WTF

 

That plug if for your OEM MAP sensor. Looks like there some crappy *** wire taps there for the GM MAP sensor you're using. Probably a loose connection there with the wire taps. Solder those wires up with heat shrink tubing, and you'll be golden. If you're not planning on ever going back to the OEM MAP sensor, then you could take the unused plug right off and solder up the other connections.