Speedometer not working
 

Just replace my speed sensor with a good used unit that was know to work. However, my speedometer still does not work. Is was working prior to top of motor rebuild, water pump, belts,rollers and head gasket work being performed. I have checked all fuses and I am baffled at this point. Is there something such as a wire connection under the hood that I my be missing. All the other gauges in the cluster work just fine. This is on a late model 1987 944S. Can anyone help or has a solution to this problem?