w208 clk 320 x reg boot leaking

[stephen.day25@b]

any info where drain holes or pipes are just in case their blocked.
sealed all around rear window and any where i can see where water may penetrate.
After showering the car, after a little while i get a constant drip above the left rear wheel arch, behind the lining in the boot, it may be coming in this side as the car is sloping to the left. any suggestions
as it affects the cd player