This might help. Third graph down.
Last year I used the book that they give you at the put in, but it is best described as 'thin'. There must be better options out there. Perhaps a River Maps? I have one for the MFS/Main Salmon and it seems serviceable.
I have only run it at around 15000. From memory, at that flow (and lower I think) for the 2 class 4's I advise what my brother-in-law (he guides Hells) calls the Oregon Sneak. Start river left and end river right. Waterspout can get tricky in lower water and there is a pour over (Rush Creek? Brush Creek?) on river left that might get you if not paying attention. I have little experience but did OK buy listening and watching others.
One last thing, you should definitely scout Wild Sheep and not just to look at the rapid. The scout is on river right and if you look up from the rapid the view up Wild Sheep (at least that what I think it is) canyon is pretty incredible. Others must have liked the view as well because if you turn around and look at the cliff behind you there are some cool pictographs. Very cool spot.
Oregon Hole is my favorite camp site. Watch out for poison ivy.
I've not been below Pittsburgh. Have fun!