Definitely 7M20518. California has a [searchable smog test history,](http://www.bar.ca.gov/pubwebquery/vehicle/pubtstqry.aspx) and this  plate reports as a Dodge Ram 1500 4x4, which this truck is.

Year shows as 2003 or 2004, and this body style is consistent with those years.

http://i.imgur.com/nFSWJ.png