Your nose and tail rail marks can vary by the nose and tail depending on the type of board you are shaping. In a high performance shape you will have a rail mark at the nose that is 1/2" and the center and tail marks at 1" to account for the foil of the board as shown here
Each board can be a little different so don't be afraid to adjust the numbers slightly to account for the rail thickness you desire.
Reference:
Simple Rail Bands Chart - (midpage)
Boxy Rail Bands
Knifey Rail Bands