For a couple years mine have been extremely toed-in with the flashlight being about 1/4 inside of the OUTER edge. I've been sitting a little closer than equidistant. But, both speakers are not mirror images of each other. The right speaker is about 4-1/2" farther from the front wall than the left. Why? Center of image. Watch the video referenced below.
I came across a speaker setup explanation presented at the Rocky Mountain Audio Fest. I was hesitant to try it for months after watching the video, but then I decided it was time. No tools, only ears. I did exactly what was said in the video and came away with a great soundstage. My room is a multi-purpose great-room with the system close to the right wall, so the left speaker is in the middle of the front wall. Nothing equal about it. But the soundstage is great! I get fooled often by sound emanating from beyond the speakers, and this has been with minimal room treatment (which I'm currently working on, so I'll need to re-tweak the speakers).
I highly suggest watching the entire video, otherwise know that you'll be missing some great info. But the speaker setup begins at 18:05 minutes into the video.
So I'm using physical placement for centering the image, not using Levels.
Watch the video and play the song that's mentioned.
The processor levels for both channels are equal.
The processor distance settings for both channels are equal.
The physical distance of each speaker is not the same.
The Toe Angle of each speaker is not exactly the same (distance changes the flashlight incidence so can't be used the same way, but it's close).
The Rake Angles are the same.