right basically you cut the wire to the dip beam on the plug send that to a relay (+side of the coil) then to earth, then link the plug through the normally open side of the relay contact then to the 12v+ on the battery, then you get full 12v to the lamp rather than the 9ish volts that you get through the factory loom, you need to do this to both sides so to relays are needed and relevant wiring easy peasy!!! just make sure you get some decent relays!!! i have now!!
(basically its how youd wire up spot lights etc but running orig lamp off old lamp feed)
