Mods: somebody please make this a sticky. I get questions about this every couple of weeks, and I'm sure other people do too. I would like to have a comprehensive thread covering this that people don't have to search too hard to find.
Gauge Cluster lights
There are a number of options for changing the color of the gauge cluster. The most popular is by replacing the gauge faces with the reverse glow faces from procarparts.com (commonly known as the PCP gauges). These fit any Protege '98 and up. They are reasonably cheap, about $40. You can get them with silver or white faces, and they have an inverter switch to light them up blue or green.
PCP Gauges installed on a 2003 LX. Note that these are on the blue setting.
These do have drawbacks. The biggest one is that it is very easy to break your gauge needles, particularly the temperature and gas gauges. As far as I know, nobody has figured out how to fix these once they've been broken. Another drawback is that these cover the gas light, the door open light, and the airbag light.
Additional reading:
Gauge Installation How-To
Info about fixing broken needles
More about fixing gauge cluster
More info
Speedhut.com also makes gauge overlays for the Protege. These have several advantages over the PCP gauges. They come with many more options as far as background color and light color goes. They are customizable with any logo you want to put on them. They don't cover the gas light and door open light. However, they are more expensive, at $69.95 base price (without customization). They come in either MPH or KPH, but don't have the other one smaller inside (could be an issue for people who travel between Canada and the US).
This is the sample picture from their web site. I haven't yet found anyone with them installed on the protege, so I don't have any other sample pictures.
Import Car Parts Plus also sells overlays. They make custom ones as well, for around $30. However, theirs don't display KPH inside and cover up gas light and door light. I don't know of anyone who has used these either.
Sample picture from their website.
Another fairly popular option is to change out the light bulbs in the cluster itself. There are four bulbs that need to be changed. They are on the back of the cluster, located approximately where they are marked in this picture.

The two inner bulbs are #194. These are large size bulbs. The two outer bulbs are #74. They are fairly small. They come from the factory as clear incandescent bulbs. Some years they had colored condoms over them, others were bare bulbs and colored by the factory gauge faces. These can be replaced with other incandescent bulbs or LEDs.
There are some drawbacks to each of these options. The light shines into the edges of clear plastic pieces in the cluster, and is dispersed through these. LED's produce light that aims straight out from the end, and so very little of it actually goes into the plastic the way it is intended. Because of this they produce "hot spots": highlights directly in front of them with darker areas around. However, the LED's are brighter and the colors are clearer than incandescent bulbs. If you use the incandescent bulbs, they will produce a more even light, but the color will be more affected by the tint on the back of the factory gauge faces. Also, putting a different color bulb in (incandescent or LED) will affect how bright the gauge needles are. They are still visible, they just don't stand out as much.

This is not from my car, but it looks about the same. I will try and take a picture of mine tonight.
To buy LEDs I recommend superbrightleds.com. They have all the parts you need and great customer service -- I received my order in two days. If you decide to buy incandescent bulbs, Schucks or Radio Shack usually have what you're looking for.
Additional reading:
The original post about LEDs in the gauge cluster
Gauge Cluster lights
There are a number of options for changing the color of the gauge cluster. The most popular is by replacing the gauge faces with the reverse glow faces from procarparts.com (commonly known as the PCP gauges). These fit any Protege '98 and up. They are reasonably cheap, about $40. You can get them with silver or white faces, and they have an inverter switch to light them up blue or green.
PCP Gauges installed on a 2003 LX. Note that these are on the blue setting.
These do have drawbacks. The biggest one is that it is very easy to break your gauge needles, particularly the temperature and gas gauges. As far as I know, nobody has figured out how to fix these once they've been broken. Another drawback is that these cover the gas light, the door open light, and the airbag light.
Additional reading:
Gauge Installation How-To
Info about fixing broken needles
More about fixing gauge cluster
More info
Speedhut.com also makes gauge overlays for the Protege. These have several advantages over the PCP gauges. They come with many more options as far as background color and light color goes. They are customizable with any logo you want to put on them. They don't cover the gas light and door open light. However, they are more expensive, at $69.95 base price (without customization). They come in either MPH or KPH, but don't have the other one smaller inside (could be an issue for people who travel between Canada and the US).

This is the sample picture from their web site. I haven't yet found anyone with them installed on the protege, so I don't have any other sample pictures.
Import Car Parts Plus also sells overlays. They make custom ones as well, for around $30. However, theirs don't display KPH inside and cover up gas light and door light. I don't know of anyone who has used these either.

Sample picture from their website.
Another fairly popular option is to change out the light bulbs in the cluster itself. There are four bulbs that need to be changed. They are on the back of the cluster, located approximately where they are marked in this picture.
The two inner bulbs are #194. These are large size bulbs. The two outer bulbs are #74. They are fairly small. They come from the factory as clear incandescent bulbs. Some years they had colored condoms over them, others were bare bulbs and colored by the factory gauge faces. These can be replaced with other incandescent bulbs or LEDs.
There are some drawbacks to each of these options. The light shines into the edges of clear plastic pieces in the cluster, and is dispersed through these. LED's produce light that aims straight out from the end, and so very little of it actually goes into the plastic the way it is intended. Because of this they produce "hot spots": highlights directly in front of them with darker areas around. However, the LED's are brighter and the colors are clearer than incandescent bulbs. If you use the incandescent bulbs, they will produce a more even light, but the color will be more affected by the tint on the back of the factory gauge faces. Also, putting a different color bulb in (incandescent or LED) will affect how bright the gauge needles are. They are still visible, they just don't stand out as much.
This is not from my car, but it looks about the same. I will try and take a picture of mine tonight.
To buy LEDs I recommend superbrightleds.com. They have all the parts you need and great customer service -- I received my order in two days. If you decide to buy incandescent bulbs, Schucks or Radio Shack usually have what you're looking for.
Additional reading:
The original post about LEDs in the gauge cluster
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