Hey guys. I just bought a used BBK x pipe on craigslist yesterday. It has not been used much and is in great condition. There is a tad bit of rust on the inside and outside but nothing to be worried about. Its also a little dirty on the inside. The x pipe has one set of cats on it. I was wondering what are the best products and the safest way to clean the inside and outside of this x pipe without ruining it? I just want to clean and maybe remove the rust if I can before I put it on. Thanks!