You need to screw the green bung out the gearbox as that will reveal a point on the gearbox casing which lines up with the mark on the flywheel as its the most accurate way of gaining tdc and if the flywheel aint lined up correctly nothing else will, make sure both OT marks line up on tha cam shaft and the mark on the dizzy lines up dead centre with the rotor arm. This is how I did it anyway to loose the 5000rpm limit and clear the fault code.