I haven't seen any discussions on changing street light color so I just wanted to post this for any future reference.
I have been editing the timecycle files and figuring out what each value does. In the light_artificial_ext_down_intensity controls the color of the street light glow, and light_artificial_ext_up_intensity controls the building and roads glow. I have my down on 0.8 1.0 1.0 and up as 0.0 0.0 1.0 and it gives the city an amazing white glow with neon blue looking roads. I just can't stop driving around looking at how clearer everything looks without that harsh orange glow.
If you have ENB installed, turning the SpotIntensity setting under to all 0.00 will remove the glow completely. Also I have light_falloff_mult turned to all 3.0000. It up's the neon look of the buildings really giving it a retro neon city glow. I am just so impressed with finding this I had to share it. Maybe I'll make a mod once I finish with the rest of the timecycle.