Come on, Dan, that is a worthless answer if he removed the spraybar and didn’t notice the position.
The hole should idealy go just below horizontal to the airflow. Across is the theoretical ideal, but tests show that in the real world. 15deg below level works best. As I recall, you can go 0 deg, 30deg or 90deg. I go with 30deg.
My guess iis that the across position is only valid for linear flow. We probably have intermittent turbulent flow, so all bets are off except for real world testing.