Ahhh, I know what you're talking about. Those kits can give variable results. What I did, when I was modding my case, was orderd 250 blue 5mm LED's in bulk from Hong Kong for like 12 bucks, they came with 120ohm resistors. I hand wired them to the 12v line on the molex, and hotglued them in place in the inside of the case. They give you the best controll over illumination too, you can keep certian spots dark, have UV LED's shining on you're UV wire-wraps, etc.
This is my old case, I eventually wound up selling on ebay for quite a chunk of change. The window is actually two layers of accrylic. With a dremel, I etched the first part of the schematic on the one, and the second part on the others. With LED's I individually lit each piece, giving it the dual color look.
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