Dodge Repair: B/U Lights, terminal pins, negative cable

Question
Would you tell me where the Switch for the B/U lights is on a 2003 1 Ton long wheel base diesal with the 6 speed manual transmission.  The B/U lights started to get hard to come on when I put in Reverse, had to wiggle the shifter just right, but eventually quit all together.  I suspect it's a switch

Answer
DIAGNOSIS AND TESTING - BACKUP LAMP SWITCH
Disconnect and isolate the battery negative cable.
Raise and support the vehicle.
Locate and disconnect the engine wire harness connector for the backup lamp switch.
Check for continuity between the two terminal pins in the backup lamp switch connector.
With the gear selector lever in the Reverse position, there should be continuity.
With the gear selector lever in any position other than Reverse, there should be no continuity.