Wanhao Di3 Cobra Fan Blower->40mm Adapter

I've been using the cobra fan (v39 @ http://www.thingiverse.com/thing:1090433) for sometime now and it's a great duct. My complaint has always been the crummy 50mm blower that mounts on the back. I never liked how far back it stuck out, nor how loud the fan was. I would get awful vibrations and sounds when the fan would go bad. So I had enough of it. Rather than design a new duct, I felt an adapter was best.

The original CAD model is available in Onshape shoudl you want to change someth