Just another idea for you to consider....
I never really noticed this issue until I got a Vive. Then I immediately felt like I had my face mashed against the windshield in the A-10, and looking under my own armpit to adjust the lighting panel and everything was just a pain.
So I centered the view so my head was where you describe above, you know, against the headrest, and all is fixed.
I agree, the view is cut off if using a monitor but it's not in the Vive.
If i close my right eye, I cannot see the details on the left of the HUD, if I close my left eye, I cannot see the details on the right.
But with both eyes open. I can see everything. Your brain overlaps them and sorts it out for you.
I'm going to take a stab and say this is how it works in RL.
Eg. In the BF-109, the gunsight is on the right, and the glass is very small, not large enough for you to look threw with both eyes, so you only use one! Your brain figures out the rest.
So, maybe redraw your diagrams for two eyes, see what you get?
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