How to extract only the car model from the demo file to apply rigacar addon

Hi I am new to blender and rigging and I want to apply the rigacar addon on the demo file BMW27 : https://download.blender.org/demo/test/BMW27_2.blend.zip

The file had many other objects which I don’t want … I need the car’s front facing the -Y axis. I tried deleting objects and experimenting stuffs but I failed terribly…

Please help me and I would also appreciate if you could give me the edited file.
Thanks