Mostly class IV. One portage before the first box. One crux drop in the first box, at 1200 it was a V or a seal launch portage (IV+). Rest is IV. 4 miles of flat inbetween the two, and a hike out point to do it in two days with light boats. Second box is more blind, but paddling is still only IV. The most blind drop should be run on the left channel, and then cutting back to the center of the river. Not hard. Lot's of moving flat on after the boxes (like 8ish miles). You can do it in one day if you hike in from the side road, where there is a trailhead. Hike along the left rim of a drywash, and it drops you into the canyon above the good rapids (cutting out 5+ miles of flatwater).
Spotted three beavers and two deer (seperate) swimming the river.
VERY worth the trip. DO IT.
Check out Cottonwood Creek nearby, and Left Fork Huntington on day 2.