Is it just the light out on the odometer? If so, it's just a bulb, #195 I think it is...but don't take my word for it. Take-out the burnt bulb and go to an auto parts store.
The dash has I think 11 or 12 bulbs that light-up the different warning lights, backlights, etc.
My daughter's 94 Sunbird recently had 5 of these burnt-out. Take the trim off the dash, take the 4 screws out of the dash panel, and the whole dash panel with speedometer, etc. should just pull-out, there's no cables, wires, etc., it has a built-in plug, and the bulbs twist-plug into the back. Most the screws are torx, but a good allen wrench will remove them.
Good Luck, Steve W.