I can't speak for Jordan, but I build one very similar that swivels. I did not use plans, but just eyeballed pictures of others and built it that way. I would love to take pictures on how it works later and share them, if you are interested. I can tell you that the majority of the swivel section is just a lazy Susan with a whole in the center, and one of these runs through the center: http://www.lowes.com/pd_31566-143-10-6BK_6_?productId=1082997&Ntt=sink&Ntk=i_products&Ns=p_product_price
|1&pl=1¤tURL=/pl_$50%2Bor%2Bless_6__s?Ntk=i_products$Ntt=sink$Ns=p_product_price|1 It runs straight through the top and the bottom of the 'lazy Susan' base (with a small groove to help it be flush), and with a small amount of grease, it can make the whole thing spin smoothly. A 1.5" (I think) PVC pipe fits perfectly into the Tailpipe and can connect the tube to the window. This way, the Tailpipe can actually spin with the lazy Susan, and the PVC can remain in place, and they fit so well together that the bees arn't able to gunk it up and stop it from spinning.
Again, I would be more than happy to take a few pictures of it in the future (when I am at home and have access to my camera).