If all the lights went out in the instrument cluster and you have replaced the fuses then there is a good posibility that it is the rheostat.
On the face of the instrument cluster, below the speedometer, are two very small knobs. The one on the right controls the light intensity for the cluster bulbs. (the rheostat)
Sometimes this knob gets bumped or inadvertently moved to the off position. You can check it at night or in a dark garage. Turn the headlight switch to the on position. Twist the knob back and forth to check to see if the bulbs are activated by the rheostat. Keep trying if it does not work. . .sometimes they are stubborn.
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