I believe these are factory correct for all 1989-1991 Daytona Shelby, but not 100% certain.  I know for sure they are correct for all 1989 Daytona Shelby.  These are silver in color.  
 
You will receive the pair.  We only have this one pair in stock. 
 
They measure approx 18"x2".  I don't know if they are OE Mopar or a reproduction.  In either case, they look identical to the decals currently on our 1989 Daytona Shelby shop car.  (that car is White with grey ground effects, with T-bar roof) - see pics