It really is this easy ! I fitted a 10amp diode between fuses 6 and 8. Note the direction. Now when the ignition is on the front and rear sidelights come on and the headlights come on dim dip. The dashboard lights and number plate lights do not come on. The only downside is that the lights are on regardless of whether the engine is running or not. I have run the car like this for a good few hundred miles with no problems. I will fit the diode properly to the underside of the fuse board shortly.