Doews anyone have a good design for a mallard nest cylinder. Most importatnly, does anyone have a good system for mounting them on a pole. I usually use a big piece of conduit that I drive into the marsh with a post driver, then mount the cylinder to the top. I always have difficulty mounting them, though. Looking for a new system, and any input would be appreciated. thanks.

There is this:
http://www.npwrc.usgs.gov/resource/wildlife/ndblinds/mallard.htm