You need to fit the phase sensor and turn the engine untill one of the pointers is in line with the optical eye part of the sensor then adjust the gap between the two by moving the sensor untill you get 0.3mm gap using a feeler gauge. I,ve forgotten which way round the wires go on again but i can tell you that they sort of cross over between the sensor and the plug if that makes sense. I,ve been told its a lot easier to remove the dizzy to fit the new sensor but it can be done in situ if you have a lot of patience LOL .The screws will have become magnetic over time and can be a right pig to get back in the holes .