Thats for the phase sensor that dude i think. I've had some bits made to do that part (very trick bit of kit, using a zetec cam sensor. cheap too)
Just need to find/have made a bracket to read a 4 toothed pickup on the crank pully itself, been told that a grp A esos cps bracket will fit with a little modding, but i've never seen one to see if thats right or not