A buddy and I are running a piece of the Owyhee April 11th-16th. (2014) Possibly from somewhere on the East Fork down to Three Forks, but still working on route options.
Class III to IV is possible depending on flows (likely to be low this year given snowpack…)
There are lots of unknown hazards. Potential for some nasty portages. Not really a beginner trip. Previous multi-day packrafting experience advised. You should probably thrive on a small amount of suffering.
If you are interested in hiking and paddling this with us give a shout or post here. eladkcem AT yah00 is my email.