I've been wondering if you could make the mount in such a way that the fan could be the support for the shelf on the one side or maybe just have two fans as the legs supporting the shelf with a slower speed. It isn't fully worked out in my head, but I imagine the shelf would be sit flush between the fans since the j-head would be directly attached to the extruder. Maybe the shelf would be a box with no top and bottom turned on its side. Attach the box to the carriage plate from the back of the carriage plate since you wouldn't have room to mount it from the front and the screw the fans on either side.
Another thought, if the shelf was made of metal or something, it could sync heat off the stepper and into the path of the air flowing below providing some cooling. Maybe we should try to talk bdring into creating another extrusion just for this.
Do you have any ideas how you'd think it could work?
EDIT: Actually, maybe we could just slide the fans into some square tubing with spacers between them. You could even cut the pipe at an angle maybe and reorient the one fan down with some spacers and my be some elastic pulling the fans together. I'm not sure that makes sense, but I have to get back to work.