Well, I know there are a lot of red interior threads, but I tried some different techniques, and I solved the problem of having red lights in the HVAC panel wash out the blue "cool air" sector of the temp panel.
These instruction refer to the EVO IX with OEM car stereo.

Here what you need:

Scissors
Cutter
Compasses (to draw the circles)
Red transparent graphic adhesive film, C145 B and C 145 A (at least, these are the standard graduations here in Italy: let's just say it has to be red )
Red paint marker
Screwdriver, Phillips, N° 1 and N°2
Precision phillips screwdriver, for thery small screws.
Flashlight, bulb (no leds)
Tweezers
Screwdriver 0,5X3X75 mm (or anything similar in inches)
Short phillips screwdriver (about 1" long, plus handle, no more)
Clean cloth
Small box (to put screws in)
Film can (to put the blue "condoms" in)

TIME:
You need between a couple of hours and half a day, depending on how practical of this kind of work you are.
It took me about 4 hours, including the time to shoot pictures and take notes.


CAUTION:
Please read everything before attempting the procedure. Particularly, read each step thoroughly before going on, and pay attention to the warnings.
A few general warning:
DO NOT FORCE anything. Some steps require some amount of physical strength, and that's stated in the step itself.

DO NOT PRY: if you need something to add leverage or as a small prybar, that will be stated plainly in the text. If you don't see it plainly stated, then there's no need to use tools to pry open the part, and it can be removed using just your hands.

DO NOT USE PLIERS: If it is necessary to use pliers in any step, it will be clearly stated. If you need to use plyers, use some soft leather to protect the parts you are about to grip.

If, while setting everything back in its place, something gets stuck, DO NOT FORCE: make sure the various parts are correctly aligned and set in the correct order.

If screws are tough to screw back in, do not force, screw back and make sure they are properly aligned to their holes.

When placing a panel on the bench, use some clean, soft cloth as a surface to avoid scratching or marring the finish.

Put all the screws you remove in the box. DO NOT leave the box open: each time open the box, put the screws in, and replace the lid.


Now, on with the reddening of your evo interior.
There's a very simple method of making all lights red: just remove the blue condoms on the lightbulbs, paint them red with a suitable paint marker, et voila.
Unfortunately this makes the blue band in the HVAC control panel fade badly. We don't want this to happen.
Radio bulbs may indifferently be painted red or covered with red film. Red film is more uniform with the HVAC panel, but if you find the correct grade of red paint even painting them is OK.

Start with cutting a 4"X10" piece of film and stick it on the other film, actually making a double layer of film.
Now make two rings, one with 70 mm external diameter and 40 mm internal diameter.
The other 55 and 37 mm (ext and int)


Then let's start taking everything apart.
1. Remove HVAC knobs. You just need to pull out. Your hands should be enough, but if you feel pliers are better, use them.

 

2.
You will now see two screws. Unscrew them and put 'em in da box.

 

3.
Extract the panel pulling with your fingers from the inside of the knob holes.
This will pull out the lower part of the panel.
Extract the upper part by pulling with your fingers the side of the panel, first on the right side, then on the left.
DO NOT ROTATE UPWARDS! Just pull out.
You need to use some force here.

 

4. by now you'll be facing the "naked" stereo and HVAC panel. The latter has a clear plastic diffuser affixed with 4 screws. You need to unscrew them, taking maximum care to avoid a screw falls inside.
Remove the panel buttons and the diffuser. You'll see two blue things: these are the lightbulbs. Extract them by pulling with some force (DO NOT USE PLIERS! YOU'LL SHATTER THEM!)
Remove the blue condom covering the bulb, and put them in the film box for later use (if you wnat to return the interior lights to their original bluish white, for example).
Put the lamps back in their plugs.

 

5.
Now for the panel istelf.
Take the red adhesive film rings: you'll notice you'll have to trim them somewhat to adapt them to the inside of the panel. We want one on the flux direction knob ring and one on the flux velocity ring.
Once trimmed to fit, just press them home. Use a small rectangle of double layer film to cover the icon on the lower part of the temperature knob ring.
Once finished it should look somewhat like in the picture (possibly better, I didn't have anything to draw the circles on the back of the adhesive film

 

Now we'll redden the knobs: You need the graphic film again, because you can't paint them and get the proper effect.
Just cut two small rectangles of double layered film, and put one on the length of clear plastic IN the knob, and the smaller one, trimmed flush to the surface, on the face of the clear plastic.
Do not use a single piece folded over to cover both surfaces, or it will unstick and your knob light will become yellowish.
Positioning the film here may be tricky, and tweezers may help you.

Once done, put the knobs in the panel holes, take the flashlight and, in a dimly lit room, light the whole from behind and take a look at the effect. You may now change film color, or correct the placement if you see white light coming out in some point. This avoids that you have to refit the panel to the car and actually turn the lights on.

 

Last touch: the buttons.
You'll notice the icon is molded in clear plastic. Use a small rectangle of double layered film to cover the inside.
Do not cover the leds: they are to remain their original color.
5mm x 20 mm rectangles will do the trick

In the picture you see the film before being pushed inside. You can't leave it there, use the small flat screwdriver to position the film inside the buttons.

Put back the diffuser and the buttons, and screw back the 4 screws (BE CAREFUL NOT TO LOSE THEM INSIDE THE BOWELS OF YOUR EVO!)

 

Having completed the HVAC panel, we'll redden the car stereo.
Unscrew the 4 screws blocking it to the dash.
TAKE CARE THEY DON'T FALL INSIDE
Pull out taking care not to strain the cables. Unlpug the white plug pushing on its release, then unplug the antenna round black plug by twisting it and pulling. It's very tight, and you'll need some force. You may want to use pliers here.

DO NOT PULL ON CABLES: grip the plug itsefl NOT THE CABLES:

 

On the bottom side of the car front panel you'll see two tiny screws. USe the precision screwdriver to remove them, taking care to remove them so that they don't fall inside.

BEFORE YOU GO ANY FURTHER, TAKE EVERY MEASURE TO INSURE YOU ARE NOT CHARGED WITH STATIC ELECTRICITY.
WORK ON A WOODEN CHAIR, AVOIDING MOQUETTE ON THE FLOOR, AND TOUCH A TAP OR SOME METALLIC FRAME TO DISCHARGE ANY STATIC ELECTRICITY YOU MAY HAVE ACCUMULATED.


The front panel is now fixed only by the small clamps on the sides. Gently lift one at a time using the small flat scredriver, starting at a side one, and remove the panel.
Do not lift them any more than strictly needed to get them free of the blocking teeth.

 

Pull out the front knobs.(The small one may be tricky, but can be done with bare hands)

 

Remove the two screws on the back that lock the electronics in place. Be careful: one of them has a small metal flat spring that should not be deformed, broken or lost. Take note of its position, so that you can place it in the same position when you put everything together again. It has anyway a small hole in which a pin inserts and helps to keep it in its proper position

Do not remove the two screws locking fixing the CD inlet frame. Once you remove the electronics, you'll see the panel is littered with blue lights. They are not leds, but bulbs. Remove the blue condoms one at a time by gently pulling them off. The one between the screen and the knob may be tricky, use the small flat screw driver to lift it with care, avoiding to break the bulb.

 

You can now choose between painting the lights or putting small squares of film on them.
Here how it should look with the squares.

Cut a rectangle of single layered film, C 145 A (lighter than the C145 B we used up to now) of 57 x 16 mm, and put it on the display.
DO NOT touch the adhesive side or you'll leave ugly fingerprints that will show on the radio display.
Position it on one end, run a fingernail in the centre for all its length, and then on the sides from the center outside so that you don't leave trapped air.

 

Ok, my wife's calling.
Tomorrow the second part, dealing with the ACD button, panel lights trim, and clock.

 

Here we go again.

We'll now see how to redden the ACD button, the panel lights trim and clock.

First we need to take out the instrument panel bezel. This is very simple: you just need to remove the two screws that fix it to the upper dash. It's easier if you put the steering wheel at its lowest position, and use a short phillips N° 2 scredriver.
Use your fingernail to lower the upper part of the bezel, and then pull it out an inch or so, then pull out the lower part and it will come off easily. Be careful not to tear the rubber flap covering the steering column.
Grab the left fake-carbon fiber panel and pull out, it will come off nice and easy.
Remove the plugs depressing the locking tab.

 

Switch the two main air vents to "OFF" so that you don't damage the internal lids when you remove the panel-vents-clock assembly.
Grip the side of the long side panel on the left. Make sure you removed the two screws on its lower part.
Pull on the panel: work on it a locking plug at a time. Do not force. Always pull outside, never lift, pry or rotate. Make sure the white plastic clips are on their plugs. If one comes off, just push it on again. Make sure no plastic clip remains in its hole in the dashboard, or when you put everything back again it will be pushed inside the dashboard.
When pulling take extreme care that you don't pull on the clock and hazard button cables, especially if the plugs suddenly give and the panel comes off abruptly.
Remove the hazard and clock plugs by depressing the tabs and pulling on the plugs (NOT THE CABLE!).