OK, I have a mystery wire that I cannot identify. It appears to be a ground wire as it attaches to the chassis just underneath the heavy metal (rusty) bracket that the resonator normally sits on on the inside drivers side frame rail in the engine bay. The wire is approximately 10" long and appears to have had some sort of connector (possibly a spade connector or possibly it pulled loose from a larger plastic connector). Here it is:

another shot
Help! I figure I knocked it loose during my ghetto intake install. I cannot for the life of me figure out where it attaches to.