I agree with you. It sounds like an ignition pack. Is there any way you can have the engine running while pulling each ignition pack to see which one is bad. If you pull one and you have no idle change then there's your bad pack. There is another way but I dont know what the voltage would be. You can test each ignition pack with a voltmeter. I'd just pull one off and if you have no idle change, put it back on and move to the next one. Be carefull though, theres enough punch in one of those packs to knock you the f#@% out man
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