Have you looked at any other additives? ChrisFix did a couple videos on CleanBoost Maxx and most saw improved MPG and he did a dyno run and saw increased HP with it. I'd be curious how it would affect your ECO project.
The Megan Racing MRS-MZ-1022 trailing arms showed up last week and after a HUGE hassle removing the old ones I got them installed. I heard the Megan arms have a tendency to rust so I filled the corners with hot glue (all my silicone was dried out), gave them a light sanding, and applied a few coats of clear before installing them.