S124 double roller cargo net/baggage cover

[MBeige]

I searched but could not find a definite answer, my problem is I need to know how to install a W124 cargo net/baggage cover roller into the rear seat. I have the net itself I just got today, and two mounting blocks that supposedly install onto the rear seat. I can see how that works but I can't find any holes in the carpet area of the rear seat backrest. Is there an illustration to follow perhaps? I found two possible screw holes but I don't want to do anything until I am certain.

Also I'll probably need to install the other mounting bits, does anybody know how to install the roof mounts for the net itself? There are supposedly four, two right above the net in the standard position and two above the same net when the seats are folded down, closer to the front. I do know that I'll also need mounting points for the tailgate, but what I want to know is do I need to get a prefabricated panel or can I just use the old tailgate panel and just cut the necessary holes to install the mounts?