But that set of wires run up and into the cab, should be reverse lights in that set as well.
But not sure the NSS is part of that "in gear" selection for PCM, wiring diagram for 2003 might help, also in IDing the wires in the cab.
Google: autozone ranger wiring 2003
They usually have some good diagrams
Normally NSS or Clutch safety switch has a pathway like this:
Battery-------key switch/PATS--------NSS------------starter solenoid
So the 12v that activates the starter is passed by the ignition switch to the NSS, if in Park or Neutral the switch contacts in the NSS pass the 12v to the starter solenoid.
Not sure the PCM monitors this but it could in the PATS part.
If possible I would start engine then remove your bypass and test if REV Limiter is still active.
Last edited by RonD; 01-17-2014 at 10:45 AM.