I suggest you shoe goo glue some stainless fine wire mesh screen on the bottom hole you drill. I was finding bugs and leaves and F.O.D. of all description in my filter after the modification. There are the baffles inside the box you can make go away as well, if you use a hot knife to remove the baffles, you will not have to deal with the plastic sawdust that will need to be cleaned out. With Epco exhausts, I was able to go to 142 main jets with the airbox opened up and a good cheap power curve gain. if you haven't already, the thumbscrew primary adjusters are a worthy investment too.
