I have a w211 e63 that I am trying to remove the factory subwoofer from the rear self. My car has the folding rear seats, so the head rest are connected to the seats. I also have the rear sun shade. I have been in the trunk and removed the c pillars, but still for the life of me, can not figure out how to remove the rear shelf cover to get to the sub to remove it. None of the searches come up with the right removal process. Please help.

Remove the top panel in the trunk. I see a couple nuts from the bottom holding something, they might let it loose. Looks like the sub will have to be twisted counter clockwise about a inch before it will lift up.

I thought those nuts were for the rear sun shade. is the rear sun shade connected to the rear deck cover somehow?

Not sure, i just happened to have the trunk all stripped in one of my cars and looked to see if there were any plastic tabs or clips but only found a couple nuts.