Every wiring diagram I've seen of my 1987 Mercruiser 260 engine with Thuderbolt IV shows four wires coming off of screw posts on my distributor (black, white/red, white/green, white/green.) However, my distributor has only three wires going directly to the ignition sensor with no screw posts. I am missing one of the white/green wires that is supposed to go to the shift interrupter switch (at least according to the pic)
I could splice the white/green wire from the SIS to the white/green wire coming from distributor, or I could leave the boat as I bought it, which has the SIS wired to the (-) terminal on the coil. Will the SIS grounding out the (-) terminal on the coil work ok? The distributor isn't a replacement, just the ignition sensor.
Thanks.
I could splice the white/green wire from the SIS to the white/green wire coming from distributor, or I could leave the boat as I bought it, which has the SIS wired to the (-) terminal on the coil. Will the SIS grounding out the (-) terminal on the coil work ok? The distributor isn't a replacement, just the ignition sensor.

Thanks.