Palacios began appearing in Westerns in the 1960s, beginning with Sergio Leone's For a Few Dollars More (1965, with Werner Abrolat and Kurt Zips) and returning for The Good, the Bad and the Ugly (1966), playing bartenders in both. He was often cast as Mexican bandits or soldiers and played Pancho Villa in Los 7 de Pancho Villa/The Vengeance of Pancho Villa (1967). Working in co-productions with Italy, Germany, and sometimes the United States, Palacios appeared in The Magnificent Seven sequel Return of the Seven (as a jailer), Dynamite Joe, Leone's Once Upon a Time in the West (with Henry Fonda, as a train engineer), Day of Anger (another bartender), Bad Man's River (with James Mason), Captain Apache (with Tony Vogel), The Spikes Gang (with Ron Howard), and the 1998 TV movie Dollar of the D