The way the fan is installed on the ANET A8 is a real mess.
In case of clogging, you"ll have to disassemble the whole thing and loose your precious Z-offset calibration...
As many of you, I don't think the heatsink is needed. To work properly a heat sink needs a good contact with the element it has to cool. Here, the heat sink is poorly in contact with the big lower aluminium part of the extruder. The size of this alu part is big enough to act as a pretty good heatsink by itself.
==> you can safely remove the heat sink...
Now we have to support the fan and make it easy to dismount to access to the gears of the extruder.
Many good options are available here on thingiverse using printed parts, magnets or so ...
My solution is for sure the simplest ever using only two M3 threaded rods on which the fan will simply slide... a Keep It Smart and Simple thing !
Replace the two M3 screws at the bottom by two pieces of M3 threaded rods. Tighten the black alu part in position with two nuts on the threaded rods.
Keep the length of the threaded rods long enough to slide the fan on those two rods. The fan will stay in position.
If you need to access to extruder's gears just pull the fan ... Et voilà
If you don't get any threaded rod in your garage, you migth as well use 2 long M3 screws, just remove the heads... If not long enough, connect two of them with a printed tube or glue them with a piece of tube, there is room enough between the fan and the aluminium block and this would act as a fan spacer .
EDIT : I've designed a small cover which acts both as a spacer for the fan and as fan duct avoiding that too much air is blown downwards in direction of the hot end. Just slide the cover on the two M3 rods then slide the fan on top of it.
EDIT : It is possible to turn the fan the other side (sticker outside in order to suck air from inside, thus avoiding pushing dust towards the filament...
my other ANET A8 mods