Sal, at one point you could fill out a form and submit the VIN to the DMV in California to request a registration history on a vehicle. When I ordered mine on E408395, it listed the CHP as the first owner and included the license plate (i.e. Unit Number). Here is the discussion:
http://www.specialservicemustang.net...California+DMV
Due to privacy laws, this option may no longer be available. But it is certainly worth a shot. Please let us know how you make out...