If you're getting no spark on ANY plugs, you may have a problem with the CDI disable circuit. This is a black-with-yellow wire that runs all over the boat. Anything grounding that wire disables all six CDI's and prevents sparking. Things that are connected to that wire include:
1) Keyswitch
2) Killswitch
3) RPM limiter (on engine)
4) "Throttle Guardian" (black box behind steering column)
If you're staring down at the top of the engine, there is a wiring harness coming up from the right (in this case, port) rear from the CDI's on that side. There will be a black-with-yellow wire. It will connect to one of the two black boxes sitting on top of the engine there, and a black-with-yellow will continue on and eventually run up toward the console. You can disconnect that wire at the top of the CDI column, next to the on-engine rev limiter, via its bullet connectors. Do that and see if you get spark. If so, check the four components listed above - pretty likely you'll find one of them is holding that wire grounded.
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