You'll probably want to hook the neon lights to a relay and then hook the control side of the relay to the parking lamp circuit. This arrangement will turn the neon lights on with your parking or headlamps.
To wire it up stop by radio shack or an auto parts and get a SPST 12v relay. Then connect the 12v input from the neon lights to terminal 87. Connect terminal 30 to a 12v fused supply such as the cigarette lighter power feed. Connect terminal 85 to ground. Connect terminal 86 to the power feed for the parking lights using a tap connector.
Typically the parking lamp power feed is a brown wire coming off the headlamp switch, but cant say for sure since I don’t have wiring schematics for a 2004. I’m sure someone will chime in that can shed some light on the parking light wiring color.
2001 Ranger Edge 3.0 V6, 5 speed M/T
Limited Slip Differential, James Duff Traction Bars
Kumho 30x9.50 15 MT / Black 297 Series 15x7 Rims