Well I see my questions on the other thread are answered here. A small branch, and a swing door, and vent holes.

Les, that is interesting. Gonna have to check that out a bit more. Just having structures I am a host to all manner of wasp, and especially those Fing Carpenter Bees who totally destroy structure in the presence of many trees. usually I am not in favor of killing critters just trying to get along, but I kill every Carpenter Bee I can. Destructive little bastiages. Wanna bore holes, do it in a tree, stay offa my buildings **@#^# Bees

I went off on a search, and immediately found this. I think I'm gonna just cut to it, and put in round holes, and just let the small birds have a starting spot. A home of their own as it were.

Looks like it wasn't a random example either.