I couldn't see much under the extruder so, I made light.
Using ultra bright LEDs and a resistor a bit of 3d tech know how and presto.
follow the photos, longer leg of the LEDs facing one way as known as positive side, join them up in series, the resistor is fitted on the red wire and covered in heatsleeve, the two wire on each end of the LEDs, cut a bit short and poke through hole, then solder the end of the wires and connect other leads LEDs. solder the black wire to the shorter side of LED, and the red wire with the resistor to the longer side of LED. Make sure there is room for resistor, best resting on the LEDs, it won't effect the light. Then test the light connect it up to 12Volts supply, if it work then you can glue the cover.
It is ready to put in the extruder. I made it to fit perfectly to the http://www.thingiverse.com/make:196385 and it should fit on E3D V6 and clones too.
Let me know if fit on any other extruder, hat or whatever?
3x LEDs 3mm ultrabright
1x resistor 270R (can have 300R or 330R)
red and black wire
AS REQUEST 10/4/16 by Sorcerer34, thank you.
I added to STL 3x 3mm LEDs for 40mm fan (updated)
you can connect to heatsink fan or you like it switch on it, it is up to you.
I didn't add the 5mm LEDs, it is slightly bigger and brighter, the 3mm one are much better, I do have STL if you want it.
need to stuck on 100% infill, PLA, no fan.