Speedometer Issues

Your speedo head needs servicing, it is binding. Remove the cable completely to check it's condition. Wouldn't hurt to remove the drive from the trans to inspect.
So I guess I will need to pull the gauge cluster then. I've never done it, can I pull just the steering wheel to get the cluster out, or do I need to drop the whole steering column?

Edit: Forgot to mention, '73 Dart Swinger.