Leak close to boot

Hi Peeps

Hope you can help, the last 3 times it has been raining hard a damp patch appears to the offside rear section, close to the boot seal were the plastic trim meets the roof liner.

For the life of me I can't find out were the leak is coming from.

Here is a list of the things I have done so far:

1.Removed Boot trim and re-seated to make sure do damage is present.        &nbs p;         &nbs p;         &nbs p;         &nbs p;         &nbs p;         &nbs p;         &nbs p;         &nbs p;   2. Removed and applied plumbers tape to the plastic gromet that covers the hole near the effected area.         & nbsp;         & nbsp;         & nbsp;         & nbsp; 3. Reduced the height of the rubber stopper feet to make sure they are not to high so the seal is not sitting correctly.        &n bsp;         &n bsp;       4. Removed the offside rear cluster to make sure nothing is sinister underneath.

Im out of ideas but its still happening

Any Ideas

Thanx