[DPJ]

From the discoloring on the back window I'll guess the glue used was cyanoacrylate, aka super glue. If that's the case then buy some of this debonder. It's probably the best shot at removing it without removing the plastic body. If it's not CA then perhaps boiling some water and placing the rear end of the body in the water for a couple minutes, and see if it comes loose, or can be picked away. Good luck and keep us posted on how it goes!