the neon is actually the shadow of the car and bike so its more brighter in midday and midnight.
how to install?
1. open txdworkshop and select open txd.
2. seletct particle.txd and scroll down to shad_car and replace the car shadow with mine.
3. replace shad_bike with mine.
4. replace headlight with mine.
5. replace headlight1 with mine.
6. save and open your gta sa.
7. go to options/advanced and make the visual fx quality to low.
8. play the game.
if you want any different colours just ask me on youtube.
EDIT: now comes in yellow orange red purple green and rainbow!