I did like you suggested with the tweeter panel and started at the bottom with a small flat screwdriver wrapped in duct tape, I ended up with 2 little puncture marks in that fragile material that covers the door panel. Better way is to start at the top actually, this way the tweeter panel comes off nicely...
Before you take off the panel, you have to remove the tweeter panel.
It's rather easy to remove, but start at the bottom - and pull it towards you and a bit up - on the picture you can see the way plastic falls into the holes.
How do you remove the gear knob in a 2010 Pro cee'd with A/T? I tried turning it counter clockwise but it doesn't move at all.