Early21,
On a side note - I think your methodical approach to figuring out things in advance is smart. The first recording I did like this I threw up a pair of 57s in XY at the back of the auditorium. It sounded like utter garbage. Fortunately it was not critical and was just for me and the conductor. I was also manning the conductor’s recorder at the time, which was hooked to two 58s spaced 30 feet apart at the back of the auditorium. His recording also sounded like utter garbage, so I was in good company!
-Tom