Mine (84 I-4 conversion faux-Westie) was flashing when I bought it.  Likely a function of it being converted to the I-4 motor..I tried and tried to get that sucker to stop flashing...Until I finally took out the whole clock and made a nice little ovoid piece of black electrical tape.  Put that right over that bulb and re-assembled the instrument in the dash.  You can't even see that black tape in there, and the light?  Probably still flashing, but who cares?
  Don Hanson