How to fit a Ford produced dog guard to my 1999 Mk2 Mondeo estate?

Hi
I recently picked up a dog guard (an original Ford accessory) from ebay but am unsure how it is secured to the body of the vehicle. As far as I can tell it seems that the side trim panels in the load area need to be removed to either gain access to factory installed anchor points or else to be able to drill and bolt the bottom of each side of the guard to the vehicle's body?
The dog guard is contoured to fit across the vehicle behind the rear seat head restraints and is only about 30cm or so in height.
Any help / advice would be greatly appreciated.