You will have to pull the instrument panel to see what the problem is. There are plenty of shops that can repair the VDO gauges in that car, or you can even order the parts yourself after you open it and see what's up. A google search on VDO Gauge Repair will get you started in the right direction.
I found the link at
http://www.instrumentclusters.com/odometer-gear.html to have some helpful tips.
Plan B would be to register the car in another state like Florida that doesn't bother with inspections.