Unbelievably it happened again last night! This is after I'd repaired it for the second time, but this time I put grease mixed with leather cleaner all over it, still they've chewed it off! The damage is't so bad this time, presumably due to the new flavour. There was a line of paw prints all along the bonnet and roof. Looks like I'm going to have to park off of my drive until the novelty has worn off, or at least until the shark fin arrives. It's keeping the neighbours amused though!