Congrats on getting an interview at UCLA - that in and of itself is pretty impressive, and you should be proud of yourself. The good news is you're getting interviews - it's just a matter of how long you want to stay in California and play the waiting game to find a job here.
I actually just moved to CA from out of state - the endorsement process is pretty easy. You go to the website of the BON in the state where you want to endorse, and the paperwork is there. For California, I just needed fingerprints, my transcripts, my license, and a $200 fee. (Grr...
I think whether you apply for endorsement before you apply for jobs depends on what state you're looking at. I applied for endorsement here before I started looking because the market is so tight. But you could just add a section on to your resume stating licensure, and say something like, "California license number xxxxxx, Washington (or where ever you're looking) license endorsement in progress."
I moved here from Kansas City - they're definitely hiring new grads there, if you're interested.