If you don't know where it is just head to Oxford Road station and it's literally outside the station at the bottom of the road (a 10-second walk). Pop into Cornerhouse and check out the exhibition on the first floor.
Having been to the exhibition I have to say it's an impressive exploration of the Civil War, and sheds light on the effect it had on Mexico; I feel I've learnt something I never would have known from history lessons in school.
Yoshua, like most artists, has focused on the question of reality and truth. It is clear in his Octopus exhibition whether they are interlinked or whether they are two separate entities that work alongside each other as opposed to together. Oh the questions of an artiste!
It's free too, so I recommend it for history-buffs, art lovers, or just to pass an hour or so mulling over Yoshua's ideas behind his presentation of the Civil War in Mexico.