I went to check the air filter on my 2001 Lazer Z HP 23hp Kaw as I have many times, but I couldn't get off one of the plastic turn nuts to remove the shield. It turns both ways, but won't unscrew. I think the metal nut inside the plastic shell has loosened itself from the plastic. I am just wondering what you recommend to get it off? I suppose I could cut threw the plastic and then loosen the metal nut. Here is a picture of what I'm dealing with.