Can be easy climbed in a 7-10 hour(if reasonably acclimatized) day straight from the refuge at Paso San Francisco. Hitchhike(always be careful with water and time on this road) to the pass and sleep in the very basic and cold refuge. It is about an extra 3or 4 km and 250m if climbed without 4x4. Keep it real!
"After the first glass, you see things as you wish they were. After the second, you see things as they are not. Finally, you see things as they really are, which is the most horrible thing in the world."
--Oscar Wilde on Absinthe