Right! Very productive day today, 99% sure its sorted.
So, before we started, been riding round with no boot interior, this included the tool kit, carpet, rear trim and parcel shelf
As the bumper is coming off for full diagnosis, rear lights have to come out. x3 T20 screws, then pull the clusters towards you. Once off, I then removed the rear wheels, and diffuser, which is held by x2 13mm nuts and x2 T20's.This left it looking like this,
Then with the wheels removed it made removing part of the rear arch liners easier. Each side is held by x2 T20's, one near the bumper join, and one underneath, and plastic washer near the rear damper. Removed,
So, once all that is off, time to remove the bumper. Quite surprised to find its just the skin, the rear crash inserts are bolted to the car. Its held with X1 20 each side, by the join to the rear quarter panel. The bumper is clipped in to the quarter panels. few swift tugs, sees them free
Once removed, your faced with this,
Bingo, found the issue,
^ Both the seals round the vents have split and perished, you can see them just hanging off. Water runs down the boot channel, straight on top of these. These clip into the box section which fills with water, then finds its way into the boot/tool recess........
So Removed the vents, cleaned up the area on the body work, and cracked out the clear silicone!
Then, reattached the seals on the vents,
At this point it started to rain, so never got any more pics. But basically, I clipped the vents back in, and rebuilt the car. I've just checked the boot, and there is no sigh of any more water ingress, so fingers crossed. I'll keep an eye on it for the next few days, and report any findings
Cheers