"I'm suggesting the Truckee from as early as 9AM to 4PM...dry-dropper & indicator nymphing; pocket-water & pools/deep-runs respectively. Water temps are not an issue so it can be productive all day. I've been "working" the stretch between Prosser & Boca; nice managable wading flows. If your swinging you're Spey...the "canyon" has bigger water at about 450 cfs. You'll see some adult BWO's and I believe a Mahoney Dun. If you stay until dusk, you should see some October Caddis (unverified...grapevine intel).
As for the Little Truckee; the best times for rising trout is from 11AM-3PM. The most productive patterns have been small-sized 18-24; BWO emergers & spinners. The exception can be a Beetle or Ant pattern in size 10-14...if you get frustrated with the selective risers. The water flow is low at about 45cfs. All four (4) orders of aquatic bugs are present as adults; mayflies (minimally two sizes), stoneflies (16-20), caddis (three sizes...two October Caddis observed!!) and of course midges ...down to size 72."