Other than mothballs and so-called electronic mouse repellants, does anyone have any tried-and-true methods of keeping mice out of vehicles in storage? We set traps, etc. in the area, but the pesky creatures keep getting into the cars, using headliners, seats, etc. for nesting purposes. We store the vehicles in a driveshed so can't mouseproof the building, but we want to mouseproof the cars. Help?