Can u id wire source?
 

While updating my ignition this past weekend with the Petronix modual, coil, and an adjustable vac advance, I noticed a wire that was just cut off and left. I am working on a 66 gto, non A/C car. 4 BBL model ( now has tripower). I don't have a wiring (must get one!!!!) schematic for it so I can't find the source. It is a black wire with a red stripe (possibly orange). It is located in the bundle that goes across the firewall directly behind the dizzy. I don't know of anything on the car that is not working. Any help iding this wire would be greatly appreciated.

It could be for the transmission kick down. It is black with red or orange stripe on a 67.

Thank you