There are dozens of places that you can hit North and South of interstate 80, which I assume that you would be taking back to CA. Go North in Wyoming and hit the lakes and streams in the Wind River range. Go South in Western WY and then drive into Utah and fish the Green River. You can go North on 89 in Wyoming and fish the South Fork of the Snake, The Teton, and up to hwy 20 to Henry's Fork, all in Idaho. Go an hour further North and you're on the Madison in Montana. Go further West and then North on 93 and then you can fish the Jarbidge in Nevada or another couple of hours North, get into Idaho again and hit Silver Creek and the Big and Little Wood Rivers. Colorado is a good place to start too: Rocky Mountain NP, The SF of the Platte, Chessman Canyon, The Frying Pan, and The Gunnison. Yer in Gerach territory there.
There are a TON of other, smaller and lesser known places in that vicinity that I could tell you about, but I only mentioned the famous, well documented waters that are easily accessed with only a few hours driving from 80. The other spots will remain nameless and hopefully uncrowded.
I'll be back that way myself this summer, whenever the conditions are best...and I can't stand waiting to go any longer
Cheers!
--FlyGuy (Dave)