That's still kinda confusing. I mostly run my aerco with a 722 and only rarely with the r09. I tend to run the 722 gain at 0 dB, just as I do when running any pre-amp with it (v3, bg1). A 722 at 0 will take a pretty hot signal (about -19dBFS, I think), a fair bit hotter than an r09 at 8, I think.
So what trim setting have you been running the r09 at (before and now)? In the "what is unity?" threads I've repeatedly asked "what sounds best?", hoping to generate some interest in determining that. But folks seemed more focused on a nebulous unity number. I tend to run the r09 at setting 8. Going much below that causes bass distortion in my bench testing.
Maybe with your serial number Jerry could tell you what gain each detent should be? I have a 0-50 model so it is 0, 10, 20, etc.
I run the gain on the aerco at pretty much the same setting I'd use with a v3, etc. Though the output from the aerco is a bit lower than a v3 because of the unbalanced outputs vs. balanced. On the 722 I tend to strive for peaks of about -12dBFS to -8dBFS. I typically need to add about 6 to 8dB in post to bring the peaks up to 0.