I have a B&B exhaust on my Titan. It has been on for about a year now and has alot of tar or road debri on the underside of the SS tips. I have tried bug & tar remover and normal washing. I can not get it fully clean. It is like the tar has been baked on due to the temp of the exhaust. Does anyone have any advice for getting my tips nice and clean again? I wouldn't mind polishing it to its original luster as well.