Are California Republicans really "extremely conservative" compared to the average Republican in the rest of the country? I don't think that's the case. I think it's just that they're notably more conservative than their counterparts in similarly Democratic states on the East Coast.
The Oregon and Washington GOP are not particularly moderate either. They're probably in the same place as the national party. It's just that even that makes them much more conservative than their states, they lose elections all the time, and that makes them seem like they most be extremists. Really, the states are just very liberal.