3rd Gen Rear Shelf Removal

Peoples, we're halfway through a stereo install in the lude and need to know how to remove the rear shelf. The previous owner hacked at it to fit in a pair of 6x9's and it looks a little crap.

From underneath, I see four 'tree' clips. Is it just a matter of removing those and the shelf will pop off too?

Is the top part of the rear seat attatched to the rear shelf?

My plan is to cut out a new flat piece for the shelf, whilst retaining the side bits that conform to the window near each roof pillar, then raising and moulding the centre part of the shelf slightly to match the new speakers and maybe getting rid of the window brake light entirely, as the car has a spoiler brake light. It will all be trimmed in velour a slightly darker shade than the seats.

I did the same thing for my Commodore around 5 years ago and its still looking great.