I think, IF you know the lines, the Gorge is class III at this level, except for Sunshine, which is still a IV.
But if you don't know the lines through the Sledgehammer/Boat Eater area, I think there are still class IV consequences at this level. Some of those holes could still be munchy, and the scouting wouldn't be real easy....
So, it just depends on how well you know the run.
Class III difficulty with class IV consequences.