40mm-to-turbofan adapters/mounts (for 50x50x15mm turbofans)

The point of this is to allow a turbofan (50x50x15mm) to replace a 40mm fan on any (in theory) 40mm fan shroud, on any printer. For instance, let's say you have one of these: http://www.thingiverse.com/thing:351280 or one of these: http://www.thingiverse.com/thing:356001 or heck, perhaps even this: http://www.thingiverse.com/thing:1676718 ...but you want the benefits/added power of a turbofan instead of the 40mm fan those are designed for. That's where this Thing comes into play; print the adapt