I think he was just remembering his confusion from 1967. That trailer threw a lot of people--even me, many years later. Those bathtubs in the UA marketing section have a lot to answer for. 
I was googling to see if anybody started any threads about Bill's mistake last night.
No luck, but I did find this...
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O'REILLY: OK. When you were over in Spain making those Leone westerns, which, I love those things, you know, Lee Van Cleef, Tuco, Eli Wallach, love those things. Did you ever have any idea on how your career was going to evolve? Did you have a vision going from point A to B?
EASTWOOD: You know, you just have a vision of what you'd like — what you try to do. After doing the three westerns with Leone, of which I enjoyed very much, but after "The Good, the Bad and the Ugly" I felt that it was time to get out of there. It was time for me to move on and try some other things. So I came back and tried to do some stories that had a little bit different subject matter.
Otherwise I could have been just doing one genre the rest of my life. And I don't think I'd be acting or directing films if I stuck with the one genre.
O'REILLY: You did the western thing, very successful, segued into the detective thing, Harry Callahan, and then you took the heat from Pauline Kael and these people who thought you were a fascist dog, a conservative, a terrible person.
EASTWOOD: Well, you know, everybody has their opinion, and they're welcome to it. I just happen — if you can convince somebody that you are the renegade that you're supposed to be playing, then that's complimentary in some fashion.
O'REILLY: But you never had trouble with the Dirty Harry movies with the level of violence or the vigilantism of some of them?
EASTWOOD: Well, no, the vigilantism, I'm just appealing to — we were just telling what we thought was an exciting detective story, Don Siegel and myself. He wasn't a right-winger, that's for sure. And neither was I.
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Bill seems like a fan of the Leone's ("I love those things") so I would assume he would know the difference between "The Ugly" and "the Bad". Just seems like a mistake.
Unless he was lying about being a lover of the films.
Eastwood comes out kinda pompous, as he usually does in conversations of Leone, saying that he needed to get away from the Leone territory and try something knew.
He considers
Hang em' High much different?
If you ask me he should have stuck with Leone long enough to make another good western as opposed to coming back home and cranking out lame ones.
The question is though, if Clint stuck around would Leone have made more of them?
Sometimes I wonder if he (Leone) really would have moved onto to different territory (WEST, DYS and then AMERICA) had Eastwood not left him high and dry.
