Love your idea turning a milk crate into a nesting box.
You might mention what tool you used to get such clean cuts on the side of your milk crate. I'm assuming an angle grinder but it would help if you specified.
For those that want to preserve their milk crate for future reuse you might mention the alternative of making the bottom the back end of the nesting box so that the natural opening would be available for the chicken to enter. You could then use a wood bar to create a lip to keep the eggs from rolling out.
