I was at a quick lube place a few months ago and a guy with a big Ford truck was talking about how the mice tore up the trucks wiring. He said he started using Coyote urine - I don't know where you get it but the guys working on his truck didn't care for it, lol. The thought of it in the cabin air filter makes me smile.
If you don't mind paw prints on the hood you could go with this. They love Boxster trunk trim.
