I think the only way to stop water getting into the bay is to tape over all the holes under the black plastic part. When you remove it and the sound deadening you can see all the holes.
If you do this you have to open the bonnet slowly after rains as it holds the water. This spills out the rear of the plastic when you open the bonnet and can end up on the top of the engine cover, or the coils packs if you don't have the cover. It runs out after a drive though.
If you do this you have to open the bonnet slowly after rains as it holds the water. This spills out the rear of the plastic when you open the bonnet and can end up on the top of the engine cover, or the coils packs if you don't have the cover. It runs out after a drive though.