I don't have any pictures of that at the moment but it's the middle plug in the cluster of 3. Just look at where the cam angle sensor plug is and there are 3 plugs underneath it. There is actually only one plug it can fit in anyways so you really can't mess it up. I mean you possibly can but I don't think you will.
This might help.
Here is the COPs kit:
F9 COPS kit.jpg
(starting upper left) box of spark plugs, wiring harness/electronics module, coils.
The electronic module (circled in green below) mounts to the firewall via two screws.
One end connects to the car's engine bay harness where the OEM coils do (you remove the old coils, Anthony just hasn't PHYSICALLY removed the OEM coils from the back of the engine), that path is marked in red below.
The other end of the electronics goes to the COPS that go where the OEM spark plug wires were (marked in white below).
f9 COPs install.jpg
It is PnP except for the mounting screws. Anthony has his tucked down low. Mine is mounted on the firewall.
Steven, I don't think mine has enough wire to get to the firewall. Was there anything else that you did to get the extra length?
Nope. Mine is ~2 years old now, maybe they changed it. I recall they suggested mounting the module to the firewall as a heat sink. Maybe yours doesn't need that?
They had the same suggestion but I couldn't quite get it to the firewall just on what they gave me. At least without having the wires just go from Point A to Point B and hang over the valve cover and such. Maybe there is space at the back once the coils have been removed?
Maybe? Which wire bundle is limiting the position, the COPs side or the engine bay harness side?
I understand keeping the OE coils in place to see how it works out, but I removed mine, sealed them in a bag and stored them away.
tsingson (02-27-2020)
It looks like the COPs side. I had tried to mount it where you did yours but it was just short. I will remove the coils later this evening and see what I can come up with. Did you just use self tappers to mount the module?
Yeah, I eyeballed it, marked the holes with a sharpie, pilot holes, installed.
tsingson (02-27-2020)
Cool. Still a great product though. Car definitely feels smooth in all aspects.
Does the coil seals the sparkplug holes? Can’t really see it quite clearly as pictured.
Life is short drive a Miata
yes
tsingson (02-27-2020)
Not sure about Steven's coils but mine used o-rings that I had to slide down into the holes to seal. I saw on their installation video they used to have a boot on their coils.
Mine have o rings on the coils, IIRC. They seal very well.