Indeed, might be the best solutoin. Only concern is wether they melt with the heat from the silencer(s) under the running board. I think not, however. Then you have PEEK screws, that have a melting point of 180 degrees C. An M3 countersu nylonnk should do. Inspected mine yesterday, SS screws with anti-coorosive paste. No visible corrosion after fitting them half a year ago. But if corrosion eventually appears, PEEK or nylon screws with nylon washers and then Nylocks underneath. I hav not located M3 nylon nuts so far, guess SS Nylock and nylon washer is ok. That will be the next (and hopefully final) step.