Dang it, I cannot remember the exact procedure. YOU can do a search and find out though. I believe it involves removing the knob on the headlight switch and cutting a small plastic pin off, but check this out for sure. I don't like my headlights on auto, so I have NEVER done this to any of our LX's.
Mine: 06 Mag SRT, RED 05 R/T & BLUE 05 R/T & a SuperCharger (663RWHP 300SRT)
Wifes' 06 Mag SXT, RED 05 R/T & BLACK 05 R/T & a "BLACKED OUT" 300SRT