<p>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.</p>

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.
File -->
https://www.thingiverse.com/thing:2242903