Here's the kmz file. It might open in Google Earth if you left-click it, otherwise right-click it (Ctrl-click on a Mac) to download it and save it to your hard drive and open it from there.
Not guaranteed to work. Google Earth seems to crash in some parts of Downey, particularly the area around Old River School Road and Stewart and Gray Road.
If this is your first time or you're having trouble, click here for instructions.