Be thankful you don't have an 07 like me.. not a screw in sight! For the 04, You start with the two that screw into the dash above the cluster, then work your way from there. It's not the simplest process, but far from the hardest. Like I said before, it'll be 2+ hours to do it all.
Like someone said before, the Neo size is determined by the following number 3,4,5mm. Yes you have to get a tint for the odometer, it is called "roscolux" and it comes in different shades.
I know some of the climate control lights were soldered in, but I believe the 04's are not, the one I did wasn't anyway.
I've never messed with 4th gens either.
But yes Kyle, all blue will look slick as hell. But I only did white/clear on the climate control because there is already a red/blue color strip around the middle dial, and I didn't want the blue to interfere with the red strip, as it surely will. you'll have blue and dark purple instead of blue/red most likely.. something to think about before you order. With LED's, all sales are final and there are no returns. So just make sure you know exactly what you want before ordering