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Per the California DMV instructions, you would need to fill out this Application for a Duplicate Title and submit it. It would be several weeks before it is processed, and then you would follow South Dakota's DMV instructions for transferring that title.
I hope this helps!
DISCLAIMER: This is not legal advice and I am not your lawyer. My questions are based on my knowledge of the jurisdiction where I am admitted to practice, my experience on this site over several years, and research on the relevant laws and statutes for your jurisdiction, if any. My information is not advice and you should always speak to local counsel before you act.