Where do i cut to gut my airbox?

on your first pic, where ever you see a plastic rivet, drill or cut off. Whatever falls out, throw away. reinstall shell

and on your 4th pic i believe you can leave that out too, no too surew tho

No, you need the part in the 4th picture, It holds the other side of the air filter in the box. If you want to, you could try cutting that oval out all the way to a rectangle and, if you're so inclined, you could cut the side where your fingers are in the 4th picture.

You'll end up up with the front and side cut out, with a lot off room for air to enter. Just make sure to only cut where the little fillet things are, because if you cut all the way to the edge, if won't seal against your filter anymore.