How to remove and reassemble the roof:
Locate nylon screw at rear of birdhouse
Completely remove the nylon screw
Slide the roof towards rear of birdhouse
Note: Extra nylon screw affixed to roof
Reverse steps to reassemble
Remove both wing-nuts from bottom mounting plate
The mounting plate can now be lifted off
The cleanout plug can now be lifted off
Clean out old nest and reverse process to reassemble