This design addresses two pet peeves I have had with the Taz 6: The heatsink fan is right smack in the middle of where you want to be looking to see what the printer is doing, and all the fans around the head put the print head in shadow.
This puts a 45 degree bend in the fan duct that gets the fan up and to the left, getting it out of the line of sight. It also adds two LED mounting points to allow you to wire up some LEDs to light up the print head.
0.3mm layers, 0.5mm nozzle
My first print of this was with 0.4mm layers. The slope of the funnel was too steep and loops of filament fell into the duct. With 0.3mm layers, it prints fine.
You probably want to print this with a high temperature plastic like ABS or nGen since part of this is very close to the hot end of the extruder.
The LEDs are optional
The LED mounting points can be deleted by change the value of "EnableLEDMount" to false.
If you choose to add the LEDs, you will need high brightness white 5mm LEDs. For example, this part will work: https://www.digikey.com/product-detail/en/tt-electronics-optek-technology/OVLEW1CB9/365-1177-ND/827113
For this type of LED, the flat side of the base/short lead is the negative lead.
You will also need a current limiting resistor sized to get you the proper operating current for the LEDs. For this example, I was using the 5V supply that powers the heatsink fan. The forward voltage drop of the LED is 3.2V that leaves 1.8V across the current limiting resistor. Using Ohm's Law: V=I*R where V=5-3.2=1.8V and I=0.02A, you can solve for R and find that you need a 90 Ohm resistor in series with the LED to get 0.02A from a 5.0V supply.
I put six holes in the mount to allow you to put some 0.1" diameter resistors and/or wires through the holes.
The 5V supply is not large enough to allow you to run the two LEDs in series, so you must have a current limiting resistor for each LED, and run the two LED circuits in parallel.
I tapped into the power by creating a power tap adapter in series with the Extruder cable. This way I did not need to cut any cables, and the extruder can be reverted back to the original condition. You can make such an adapter by soldering the following parts back to back and soldering wires to pins 9 and 10 at the junction to pick up 5V (9 is 5V, 10 is the return).
Even if you don't want the LEDs, four brass threaded inserts are necessary to mount the fan: https://www.mcmaster.com/#catalog/123/3329/=18ce4bf
(In case it is not obvious from the link, the part number you are looking for is 94180A331)
I cleaned up my soldering iron, set it at the lowest temperature, stuck one of these on the end and slowly pushed it into the hole. Let it cool, then trim off the plastic that squeezed out.