Extruders are Not all listed

Have setup prinetr for the Cyclops and can adjust "STEPS_PER_MM" for E0 and E1, but E2 through E4 are not accessible. Tried to program them in Marlin, but I get 100 centimeters, not 100 mm. How can you get all of the Extruders to be listed in Steps per mm? I need this to fine tune my steppers.