I replaced the screws & foam washer but it made no difference. These are the screws in the link below, they were the only place online I could find them. They are a pain to get out, you end up ruining them.

https://www.hendyeshop.co.uk/nut---a...07-30984-p.asp

NUT - ADJUSTING F1211807


I have since added silicone sealant around them & to every seam on that side of the car & touch wood, its been ok but it hasn't been heavy rain so far. The main culprit is likely to be the boot hinge area, that square section the hinge goes into. Seal behind the hinge aswell. If that still leaks, its the roof gutter but will order a new trim part before I attempt to remove mine.