February 26, 2015
http://www.statesmanjournal.com/story/travel/outdoors/2015/02/20/thrills-lush-beauty-upper-south-santiam/23768679/
describes the 8.5 mile class III-III+ section from just above Mountain House (RM 53.5), to RM 46.1 (which excludes the Monster section (which is below Hwy 20 - RM 46.1).