Bennett's Book estimates 15-20% off the Wenatchee at Peshastin gauge to call 700 to 1500 Class IV and 1500 to 2000 IV+.  I noticed on PP, however, that the max is listed at 5000. 

 

Without knowing your skill level and prior experience, I can't recommend a given level.  One nice thing about this run, however, is that you can take a look at the most difficult part of the run just downstream from the Snow Creek bridge (a short walk from the parking area) so if you feel the first rapid is within your skill level you should be fine with the rest downstream.