I have spent a vast amount of time on both the freestone rivers you mention and have tried many different ways to catch fish on nymphs to make it easier on clients. However, nothing has worked with much consistency. We do our best on assorted streamers and at times poppers.
Both of those rivers are long drainages with some stretches being really good and some being horrible depending on several factors.
If you wish to catch alot of fish and have consistent success then stick with streamers and occasionally poppers.