Changing E46 Parking Sensor

[SaBBz]

Can anyone please explain to me how to remove/replace the rear parking sensors on an E46? I've identified which one is faulty through checking the clicking but am unsure how the black strip comes off. Do I need to remove the side bits first or is there a special way of removing the main middle bit? It's hard to see how it's held in.

Thanks.

 

[SaBBz]

To remove the side strips what tools would I need? Just a flathead screwdriver?

Thanks.