I had been printing with ABS and took the advice to alter the fan so I can see the filament when I am loading it into the cold end. It was tricky but doable. I am now trying with PLA and getting it to line up with the whole is a nightmare. Can the driving cog and guide wheel be moved? A couple of mm would stop the driving cog pushing the filament off line.
I was having the same issue as you and know what you are talking about and there is a file that you should print that will help you (I have printed this).
While the file says for the Anet A6, I think the extrude are the same on the Anet A8. It goes under the gear and bearing and guides the filament to the hole. Should work well for you.
Other things that you can do is straighten out the filament. That is what I do, it helps that much more. You can also cut the end at a angle to sharpen the end with a pencil sharpener, also helps find the hole.
So try the file, I think it will help you would.
A lot of people complain on the filament insertion of the Anet A8. Personally, I have no problems at all. I cut the filament under a sharp angle and pre-bend the filament (not completely straight) and push it in the hole, it works every time without having to disassemble the extruder fan. Note that if you have the throat screwed in too much that it sticks out of the aluminum throat holder of the extruder (so not the part where the brass nozzle screws in) it is way more difficult to insert. I kept the top of the throat more or less flush with the block.
Other techniques to insert filament include:
- cutting the old filament (straight cut) and let the extruder feed while you press the new filament on top of the old filament stump, if done correctly the friction will feed the new filament right after the old,
- print filament guides for inside the extruder gear cavity,
- removable or magnetic fan brackets.