Rear Boot Spoiler

I will have one for sale soon (I hope). It has the rear brake light.
This was bought new from BMW by me and then extensively reworked to take out the ripples that the dealer admitted are common on these.
Here it is:



I am making my own spoiler to replace it.
Once I am happy with the new DIY spoiler, the OEM item will be disposed of.
The extra supports in the picture are not part of the spoiler and are easily removed.