Instrument Cluster problem
 

I have a 1986 Camaro 305 V8......the spedometer is the only thing that works one the instrument cluster, the Tach, Oil Pressure, Fuel Gauge and everything else goes haywire......I'm sure it's a short somewhere. However I wanted to see if there were any known issues or if there were any specific parts that are known to go bad that would cause this issue.