Cleaning a pennant
 

Hi guys --
I recently acquired an ultra-rare pennant from the 1966 world heavyweight championship fight between Muhammad Ali and George Chuvalo at Maple Leaf Gardens in Toronto. The pennant is in great shape but needs a thorough cleaning to remove some stains -- including a coffee cup ring. I would appreciate any advice on how best to clean it up before getting it framed. Thanks!

Can you post a picture?