ok i am a big fan of underglow kits (read: RICER), after buying a neon kit, and having it break, i moved on to LED kit but was not willing to pay 150$ plus for something i might break in couple of months. so what i did was make my own first i made 2 side tubes, and they still work after driving throgh foot deep flooded roads, and scraping frozen ice and snow with the underbody (the tubes are flexible so they can take hard impacts and still not break).
the spread out of the light did not come out great but this was corrected with the front, rear, and grill tubes, and the side tubes will be redone also. For the tube i used clear silicone hose i got from home depot. (the side tubes were zip tied because it was basicly a test to see if the tubes can survive water and snow, and impacts, and they did)
what you need is bulk package of 5mm blue led's of ebay, and a **** load of resistors so that they could be used with 12-14 volts dc. silicone hose from a hardware store, speaker wire or any other wire that can handle 14 volts dc. a soldering iron
, and silicone to seal the tubes. im not gona type too much i will just post the pics of step by step of how i made the front tube, and you guys can ask questions that i can answer later on.
i have sanded down the tops of the leds for a better light spread (with out that your under glow will look like my side test tubes)
now you just seal the ends of the tube, and its ready to go on the car.
PS: i will edit this post with answers to questions you guy will have.