I don't think coils really care which way the primary side is wired. neither side is grounded. it is mainly labeled to keep THIS from happening with people trusting the wire cuz that is what the coil terminal says. my hatteras holley elec chokes are run right off the purple wire.

you could wire in a relay and use the coil plus wire to trigger it.

I ran into a few times at the track, coils wired backward. They worked, but cars wouldn't mph until coils where wired correctly.

I get what you guys are saying about connecting to the coil, but why does it matter? There's only one ignition feed coming from the switch to the cannon plug, one out of the cannon plug and a junction inside the harness. So essentially anywhere you hook it, it's connected to the coil.

RF ring?

i think because the choke coil uses so much current is why taking it at the coil + terminal could cut some voltage to the coil but i understand what you are saying.on my wiring harness i have several purple wires that are not used and all the purple wires are a pretty heavy gauge wire,

If your choke wire is grounding out the coil and keeping it from starting you could install a diode so the ground signal doesn't back feed to the coil yet positive will continue to feed the choke.

As for wiring the coil backwards....i had a first hand example of this back in high-school shop class....teacher hooked up a scope to a properly wired coil and showed us the signal...then reversed it and the signal was upside down. also explained that the spark will be weaker running backwards and there will be drive-ability issues. reason being the coil has a primary and secondary coils inside. The common terminal is on the neg connection.....So primary coil goes from the positive to the negative and the secondary coil goes from the negative to the output of the oil going tot he spark plug. When the coils wired backwards you now have a positive charge on the output coil wire. So....when hooked up backwards the voltage to the secondary winding would have to backtrack thru the primary winding to the positive terminal and then thru the secondary windings. So the voltage to the secondary windings would be reduced by the resistance of the primary windings since it would go thru the primary windings and then the secondary windings causing lower voltage and amperage output.

Damn near every wire on a boat is 14ga. Auto engineers and penny pitchers would sh!t over this lol

Mercruiser sells engines for the amt auto manufacturers gets for cars.

Ya know I never even thought of that until now. Crazy.