Roosting bar questions -- dimensions

[C Siena]

I wish I had thought about the upside down windows. Sadly, too late.

I have the poop boards 6 inches below the roost, with 18" between roost and wall and 12" between roost and front of board.

As the dimensions of the windows are the same either way, can you switch them?
Ours are with screws into the surrounding wood, so I think we could adjust if we wanted.