ORIGINAL: Stripes
Don't use a Scotch pad. They are an abrasive. Lots of automotive engines have been damaged by them.
LOL. Thanks for the concern, but on the outside of THIS muffler, I wouldn't care if I ended up using a Brillo pad, much less a fine Scotch pad. Shoot, I'll try scraping it off with a putty knife if neither one of those work!!
