Doing a little more research, it looks like Benito Margarito Uranga's parents were Rumaldo (also seen as Ronaldo) Uranga from Mexico, and Rosa Rivas from Texas. Benito had at least two brothers and one sister - Joseph, Aneceto, and Rosa. They moved from TX to CA around 1900 or so. It appears that Joseph ended up in Ventura County, and Benito up in Alameda County by way of Fresno. Note that many of the records flip between Uranga, Urango, and back again.
If anyone has any other information, please post a reply. Thank you.
Jaime