I know you posted this a couple years ago, but this is wonderful! i showed my Hubby what you did with a wall and building the nesting boxes into it and he said he could do that! im am so excited! this was a great retrofit! i have a question though, what did you do for lighting and ventilation? we are goint to cut 2ft x 4ft openings on each wall and make them windows and cover them with plexi glass in the winter but still allow light through. and two of those spinny ones in the roof for extra ventilation.