The testers sell for less than 10 bucks at any auto parts store. But in a pinch, you can make one out of a piece of wood and two nails. It is very clunky, but will tell you something at least. Drive the nails in and bend one to make a 7/16" gap with the other. Connect one side to ground, connect the other side to the plug wire in question. Spark should jump that gap, with a strong blue snap. Personally, I never felt from post number one that you had "weak spark". I think your problems are in the optical sensor part of the ignition system. There are problems with the sensors. But then again, I am not there, and have no definitive test results to go on. What...powerpack and stator...at least 400 bucks, easy....Yes you can disconnect the harness. That will eliminate the key switch question you had. If it starts, you will have no way to shut it down, except by choking it with rags, or re-plugging the harness right quick. Have water on it for all these tests. The tester with the red knob is the type I use.
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