How do you clean the airbox? I have the basic grime and airfilter oil in the airbox. I bought an Acerbis airbox cover but it doesn't appear to be the correct one as it has a hole but no mounting screw or place to run the airfilter clip over. I am going to return it and get the Twin Air airbox cover. But I am still puzzled how and with what I can clean the airbox with. What do you guys do?