I wouldn't try to register it in Cali. A friend with the exact same truck has his imported from Canada and registered in Washington fairly easily. Most folks register their diesel toys remotely for Montana. You'll seeing old trucks and even super cars with Montana plates driving around Cali.
In Oregon & WA state, diesels are usually not too hard, with regards to emissions, if they are older - e.g., my '97 Dodge Ram 3500 with 6BT is a Canadian built truck and it has been registered in both WA & Oregon.
However, new restrictions are coming out for metro areas, such as Portland and Seattle, including the counties for those metro areas - as they are wanting to not have diesels in the city.
WA state is really strict about people living in WA but driving/owning vehicles licensed in other states due to the number of people trying to evade the sales tax and annual registration fees - which are heavy. So keep that in mind.
Calif. even more so - a LOT more so.