Scary
It works
IIRC I removed the two of the bolts that hold the trunk lid to the hinge. I think I did the driver side, though removing the battery on the passenger side may give you more room to work (the two bolts on the driver side are shown with the trunk lid open):
Click to view attachmentUnfortunately, because the rear trunk is closed, you will have to remove those bolts through the engine compartment (forward bolt shown, the other is back towards rear of car):
Click to view attachmentYou will likely have to remove the drain hose and other stuff that will be in the way. Also, I think I had to use an open end wrench on those bolts instead of a ratchet. You may have better luck than I did.
Once the two bolts are out you can GENTLY raise that corner of the trunk a couple of inches, and using a LONG extension that you've cobbled together, remove the bolts holding the lock base in place. You'll need some kind of a light to see what you're doing too.
DO NOT open the trunk lid yet! Reattach the trunk lid to the hinge first! Don't ask me how I know....
Click to view attachment