They may be burned out. The instrument cluster is backlit by 4 lights (at least in my 97) and when one fails, the light from the adjoining bulbs bleeds over, making it appear like the bulb is just dim. My guess would be that the old cluster is probably lit by 3, and the light behind those gauges is burned out.
The dealer did mine, but at least on the newer ones its pretty easy to change them.