Yikes people. No need to pull the dash.
Had this same problem this past summer. Caused by a voltage spike or an accidental entering of the diagnostic mode.
Press and hold the odometer reset button (post) 2. Put key in ignition and turn to run (NOT START). 3. When needles begin to move, release the odomoter reset button (post). Voila - speed and tach are reset to 0 on the correct side of pin.
OR
Disconnect the battery for a least half an hour.