I did it on mine this summer, and it can be a bit of a nightmare! I wanted to be able to switch the lamps on with the high beam, and also on their own. The feeds to the headlight bulbs seem to be earth switched on the 4.1, which was a !Removed! nightmare! I ended up fitting a separate foot switch on my foot rest so I could control high beam with my free left foot. I also have 2 switches on the dash, 1 for on with high beam, and one for on all the time. I wired the lamps to a relay from the battery. The relays are mounted in a box on the rack. She switch feed for these go back to the dash switches and another relay wired to the foot switch. To get the foot switch to operate the normal high beam, I just sent the output from this switch to a relay that cross connected the low and high beam wires. That way, if the headlights are not on, the foot switch can just operate the roof lights. PS 4 lights on the roof gives amazing coverage at night!