In the scene where The Man With No Name (Clint Eastwood) and Mortimer (Lee Van Cleef) are looking at each other through telescope and binoculars, Clint's binoculars look too modern... very anachronistic.

Also, in a shot just before that, you can see that some of the buildings are pure facade, not just a facade in front of a shack.

I've heard that according to Clint Eastwood, The Man With No Name's name is "Joe".

That's in A Fistful of Dollars. And it's only the undertaker who calls him that.* In this film, "The Man With No Name" is called "Monco". In The Good, the Bad and the Ugly, he's refered to as "Blondie". So technically, "The Man With No Name" does have a name in each of the three Clint Eastwood Spaghetti Westerns.

*It is also the name given the character in the credits, but at no point did Eastwood identify himself as "Joe" in Fistul.

"No, old man. Thought I was having trouble with my adding. It's all right now." - Monco