yes there is a propper loom for the disco 2 but its not cheep but it keeps every thing standard tiday and gives you the propper switches i am guessing but it wont be less than £60 and dont no realy where to get one from
have a quick look to see if its already fitted tryremoving the 3rd switch blank down on the left hand side of the guages and see if the wires are there and have a look at the engine bay fuse box there should be an extra black box at the back with a fuse stuck on to the side of it
found this link that may be of some help
www.discovery2.co.uk** Driving / Spot Lamps