6/17/18 - I finally uploaded the 2 versions and pictures of the one I had on my printer. I've replaced my mk8 extruder with the prusa style mk2.3, so I no longer use it, but I figured I had been neglecting this for too long and took some pics since I keep seeing people add it to collections and what not. There is a set for a 4mm bolt and a set for a 5mm bolt.
I also added a back plate and a cut out on the front part for a fan shroud. The back plate is just a spacer so if you have a fan that clips on the outside, it's not wedge in against the metal bracket and the fan, which kinda puts the fan at an angle. This should keep it square and make it easier to change or remove the fan duct, while also keeping this mod squared up with the bracket. I also modified the arm on the second part to account for the extra thickness of the back plate being used, so it sticks out ever so slightly more then the normal one.
Update 10/25/17 This will actually fit a 5mm screw for a hinge due to me adding a 1mm offset by accident instead of 0.5mm. I've been in the process of correcting it but my computers been down for the past few days due to "corrupt system config info" with windows 10. I'll upload the 4mm and 5mm ones just so both options are avail for anyone that might want one or the other.
I'm also adding a shim to the back of the part cooling fan, as I've noticed that the shroud that I use that clamps on the outside instead of the inside, keeps the fan at a bit of an angle since it's wedged between the fan and the bracket, that stops the arm from keeping pressure on the back plate to hold the fan closed. This shim will mean that the arm will also need to be pushed further back since the whole thing will sit about 1mm out further then stock,.
I had the Anet A8 Fan Cover and wanted to add the Extruder Fan Mod to my printer but didn't want to loose the logo, so I added the center logo to the middle of the cooler fan part.
I also couldn't find a 3mm x 50 screw at the hardware store near me, so I just bought a 4mmx50 and made the holes bigger to take the 4mm instead.
Oh, I also made a little cut out on the inside to make room for your fan shroud if you have one like me that clips on the outside of the fan instead of pressed fit inside. Hope I got those measurements correct..
This is my first remix of anything, so if I did something wrong, let me know..
I have it printing out right now, so I'll add some pics once it's done.
I ended up having to print it face up instead, as the Anet logo sticks up further and stops you from printing it out upside down like the original, but this should also give you a better finish if you iron the top.