Bumpers are easy to get off. There are the 3 screws/bolts under the bonnet at the top and if i remember right 1 in each wheel arch and one below each corner if that makes sense. think there are also 3 fixing clips underneath it, the ones you push the centre piece through to release them. Thats from memory, its been a while lol. Never had any problems with water or anything but others might have a different opinion