im with daz on this , defo a short after the switched unit , if youve disconnected all the lamp units and the dash lamps then its a chaffed wire more than likely , you need to remove the column cover and take off the multiplug for teh sidelamps , find out how many wires feed the sides ( cant remeber if there split ) then trace that part of the loom

can be a lengthy process , but youll get there in the end !!