Another custom mission for Download - Call of Juarez: Bound in Blood
Don Pedro Mendoza is a mission set in war times (American Civil War) made by Henry (presumably according to Cojmodding post with the same name, but multiplayer map instead, I don't know the map author).
You play as Ray and with your brother Thomas. You are hunting down Don Pedro Mendoza. Your main task is to capture him, and deal with some Mexicans too along the way!
Put the .pak file to Call of Juarez Bound in Blood / COJ2 / Data / Mapsextra