Those are definitely NOT the rusty chains for Grunting Gringos Those are for Less Than Zero.
There was confusion about the FA in the Ruckman guidebook concerning Grunting Gringos. Brian tells me that he and Bill got the 2nd ascent of the route and he cannot remember how they got down. I would assume he used the shrub that has been removed or continued up the chimney.
3 Amigos (climber just below the crux) with Mexican Crack to the left and Grunting Gringos on the right. The rusty anchor chains for Grunting Gringos are visible in the top right of the photo.