Sounds like just the odometer and clock light then. The clock light is easy to replace. If I remember, it's just two screws at the bottom of the ac/stereo panel to remove it, then you can replace the light. I've never taken the guage cluster apart but I'd imagine there's a backlight for the odometer.

Edit:


According to this it looks like you might be able to remove just the clock portion rather than the whole panel.

The guage cluster is another story though. It looks like you'll have to further disassemble it once you get it out to get to the odometer light.