| All Dukes from '04 onwards have the light switch blanked off.Drain on the battery is not a problem as the lights go out as soon as the starter button is pressed.The lights and ignition also shut down after a while (15secs?) to save power if the ignition is left on.
MY '02/03 bikes had the light switch fitted,I'm guessing the switch should fit straight on to a later bike.
For track days its a fairly simple job to remove the lighting fuse.(I think its the first one nearest the h/light.) | 
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