Have you also got a roof aerial? Very common source of water coming through the interior lamp etc. Cure is to remove the aerial and refit with silicone sealer.
Hi Craig,
I removed the aerial from the roof and then sat it back down in silicone.
Managed to unbolt it by removing the interior lamp assembly for access.This worked ok on a ZX Citroen and a pug 306.Hopefully you will be able to do the same.Geoff