try touching the wire that was cut to anything that is grounded. make sure you have the lights on and if it works then you just have to keep it grounded. if it doesn't work then you need to find a positive wire to run to it.

 

You will just have to use a multi-meter or a test light and find a wire in the harness that is hot when the parking lights are on. Wire the center bulb contact point wire to that. The other wire goes to a good ground.

 

well I fixed the tail lights and the license plate works!! The battery wont hold a charge though It wants to fire up but not enough juice.

 

dodge trucks seem to really like there juice. i leave mine on trickle charge all the time. hopefully it will extend the life of the battery.