I don't really know much about Boot Hill, though I've always been interested. Boot Hill and Gangbusters were the two TSR games that I never played or owned; to one extent or another, I think I've played almost everything else they put out back in the day (D&D, Gamma World, Top Secret, Marvel Superheroes, Star Frontiers, Indiana Jones).
I know there were two different editions of Boot Hill that came out back in the day, and I remember flipping through the second edition (which was a paperback, as opposed to the original boxed set) and seeing stats for such famous NPCs as The Man With No Name, Paladin, etc. I want to say that the rules in that edition were more D&D-like in format, but I'm not really sure. There was also a magical item in the Book of Wondrous Inventions that allowed crossover between Boot Hill, Top Secret, etc. and D&D worlds.
I really should check Boot Hill out myself, now that you mention it.
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