Well I will be lighting up my interior and I have a pretty good idea of what all I need, I just need some opinions on colors and whether to used cathodes or led's. For underglow i'll use led's. I've been talking to people and aksing this question and I was told cold cathodes will put out more light. Thanks for the help!

This is everything I plan to light up

Borth front grillesdunno how many cathodes i should use any help?
engine - dunno how many cathodes i should use any help?
footwells - two 12" cathodes
cargo area - two 12" cathodes
cupholders - two prewired led's
air vents - 1 led per vent

well first tell us what color your car is

Flint mica.

Anyone got cathode or led advice on sizes?

The cathodes should be fine as you have it. You can also easily put some under the front seats.
I have two in my engine bay, it honestly could use one on the radiator support to light a little better.
Here's the only real picture I have of it, its brighter than it looks in the pic but still dark in the middle: http://i7.photobucket.com/albums/y270/DARKSANDMAN/P1000270.jpg

I would say green lighting always looks cool, but if you do that you'll have a hard time getting other things to match it, since green just isnt as common for accessories.

I just installed some LEDs today in the two center vents, and door handles, and cathodes by the feet. I havn't had time to do the two side vents and cup holders yet.

I got a switch from Oznium.com (the big black one all the way on the right) and got some wires and all the LED's there. 5mm blue, with the plastic holders. You also need resisters to sodder all to them too. The door handel ones are the only ones that are not on the switch, because i havn't had time to run a new wire all the way threw the door.
http://www.cowsgomoo272.com/tc/smaller/tn_100_0512.JPG
http://www.cowsgomoo272.com/tc/smaller/tn_100_0517.JPG
http://www.cowsgomoo272.com/tc/smaller/tn_100_0516.JPG



I got those two smaller switches from auto zone, and the LEDs in them were waaaay to bright, so i disabled those and put two 5mm LED's on the extra blank.
Your question about getting the power; i ran a new wire from the battery to behind the switches, and went in the switch, and then out to all 8 locations. That is to many wires to come off of one switch though, so i used a distribution block to devide the output of the switch, because it's really hard to crimp 8 wires together and connect it to one switch.

I guess i should have made a DIY out of this...lol, oh well. Next time!

I forgot to also mention, for in my enginbay, i used led strips, rather than cathodes...I got a stronger light out of those, and they are more durrable on the exterior

I'm still getting mixed reviews on led's or cathodes for the grilles and engine bay. When I do my vent led's I think I am going to drill the hold for the led further back so you can't see the bulb and only the glow, I may go with a brighter led for glow.

Anyone have a white light setup they could post?

I'm still getting mixed reviews on led's or cathodes for the grilles and engine bay. When I do my vent led's I think I am going to drill the hold for the led further back so you can't see the bulb and only the glow, I may go with a brighter led for glow.

That's what i was going for when i did mine, but once i got in there i realised i don't have to many options, lol. I though I got it out of sight pretty well, but depending on what angle the vents are pointing, you can still see them ( for the pic, I adjusted the vent so you can see it. The two side vents are goign to be tricky, I havn't done those yet. any one that has should post some pics.

Does anyone have a white setup they know about? Also I am going to be painting the center console/hvac area to match flint mica. I was wondering if it would go well with some sort of metallic white? pearl perhaps?