Actually, it's not. The "Dollars" series starred Gian Maria Volonté (as "Ramon" in
A Fistful of Dollars and "Indio" in
For a Few Dollars More). He was absent from the third and final flick (
The Good, the Bad, and the Ugly .....which didn't contain the word "Dollars" in the title anyway).
The "Dollars" series comprised only the first two of the Leone/Eastwood trilogy.