In my car the whole bottom of the boot is some kinda fibreglass or plastic... including the spare wheel well. Don't really know where you mean Drocay...
Mac I spent a while checking it out tonight & I think I will do the same... I pulled all the panels, the wheel, and the carpet out, and I seriously could not find a single bolt that's going onto metal in the boot area ... other than the 3 strut tower ones on each side. For the time being there is a macgyver style ground running back to the front of the car >

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