I have been happy with innovate's products. If this is something for the coupe I would recommend two of them. I was really surprised how different the two banks on my car are when I added a second sensor. With 8 carbs you can dial that in pretty good if you have the info.
The two banks might not have different AFR, you might have an exhaust leak on the side that reads lean. Or you might have one wideband that is reading off. You can swap the sensors side to side to see if the problem follows the sensor or stays with the side. If it stays with the side then I'd bet you have a small exhaust leak.
We see this all the time on the dyno and I've never found the issue to be with the engine. It is always with the sensors or the exhuast system. Most engines just don't run richer or leaner on one side than the other unless the induction system is really strange.
