lexus-is2

My left exhaust heat-shield that sits above the oval shaped exhaust muffler seems to have come loose. It seems to be just resting completely on top of the muffler. Doesn't seem like it will easily fall off but don't want to risk it. I went under the car to try and figure out how this is attached but couldnt see has it is above the muffler. Can you actually re-attach this without removing muffler?