Would like to know whats a good way to clean my Headers on my 93 sl????. Thank you.

 

Externally or internally?

 

Can you give me both examples??, thank you

 

These are examples I pulled from Google -- elapsed time 3 minutes -- Google is your friend
FYI the S car exhaust manifolds are cast iron.

No clue if any of this works and not responsible for anything that happens if you try any of it:

Outside
https://www.autoanything.com/exhaust...xhaust-headers

Inside
https://www.yesterdaystractors.com/c...oolt&th=320668