Damn, the creator was Ryogo Narita before Ryogo Narita. Making an anime set in old times America. I read the manga as it's illustrated by Hitoshi Ariga, who made the Rockman Megamix mangas. Ah I love that guy. But I didn't know he illustrated this!
I own both the Bandai Season DVD's and the Blu Ray set. The Bandai version still contains this Opening while the song was replaced with "The Show Must Go On" on the Blu Ray set. Was Big O really replaced for legal reasons?