The attic fan I referred to was purchased from a commercial HVAC vendor. It was in its' original packaging. There were no parts missing; it had not been cannibalized.

The wires came out of the motor through a permanent bushing. There was no place to mount a box, or fitting of any sort. The arrangement was similar to this, but without the flex:

http://forums.finehomebuilding.com/...ttach_images/211272/img_0126_600x800.jpg