Start at the source and work out. If you've got spark being generated at the stator, and it is making its way to the coil, then check the coil. You said you had a manual, so look in there for the test specs. If it checks out, then check the plug wire and cap. If thats good, try the plug in another engine, or another known good plug in yours. Also try to check the spark in dim light, as it makes it easier to see. Also disconnect the kill switch to isolate the possibility of that killing your spark. The only part you haven't replaced thus far is the flywheel, which if the magnets in it are weak, can kill the spark. Check the other stuff first though, as flywheels rarely go bad. I suspect you've simply got a bad connection somewhere.