For those looking for an after market rear mounted table for the tail gate, Front Runner makes a very nice one that also has a pull out bread board which doubles your working space. They originally made these for the Jeeps and when I first purchased my 2020 Defender I drove out to offices/warehouse and purchased one and showed them how I was easily going to adapt it by drilling matching holes to fit the Defender existing screws. They have since added these holes and now you can buy one that fits a new Defender. I am sure they will add additional holes to match the new Grenadier as I am going to make the same trip again when I get my Grenadier and let them pattern it.
When I fit mine to my defender, I simply bought an extra clear piece of acrylic and put it up agains the rear door and carefully marked with a permanent marker where all the existing screws where on the New Defender. I then put the acrylic up to the Front Runner Table and choose the best place to drill holes on the backing plate. I then simply removed the screws at the rear door of the New Defender and used those to attach the new Front Runner Table. Note: I also purchased some large rubber fender washers and put them between the backing plate of the Front Runner Table and the back of the rear door for two reasons. One was to equally shim out the backing plate on the Front Runner Table so it would set vertically on the rear door and the other reason was to stop any possible vibration.
Note: If installed on a Grenadier, you would loose access to the first aid kit at the rear door, however you can easily relocate that to the boot.
Here's a link to the Front Runner Drop Down Tail-Gate Table to view it.
DaBull