Also decided to have another go at removing the tow hitch. Gave it plenty of spray, wiped it off, there's a name, Witter. And, oh look, a key hole! That's why there's a little key on each fob! Now I just have to wait for the GT85 to free up the keyhole cover slide. Then, if Youtube and the official Witter instruction video is to be believed, it will obediently fall into my hands. And crush them on the floor, looks heavy! Then at some point, I will set about removing the rest of the mount. I'll leave the electrics alone, though, too much scope for errors.
I also managed to free off 5 wheel bolts.