If you have done all that they have suggested which were all correct, remove the coil, sand or file the two bosses that stick up on the engine and the coil where it connects to them, re set the gap and use a screwdriver inserted into where the plug goes hole it close to the frame to see if it will spark, of course with the kill wire removed and if this does not work it is the coil, they need a surface ground, bolt will not give a proper ground, good luck, Joe