To answer your question, I’m not sure the improvement in two-channel listening would make it worth the trouble. The rule of thumb for optimal two-channel listening is the equilateral triangle, where the distance between the two front speakers is the same as their distance from the listening position. You mentioned the LP is 9’ from the speakers, and from your picture it looks like your speakers are pretty close to that distance apart.
It would be easy enough to move the speakers to the proposed location for a listening test. Why don’t you try that?
Regards,
Wayne A. Pflughaupt