2008 f350 water leak
 

Hi folks,I have a 2008 6.4 F350 extra cab shipped from the States to Scotland.I have a small water leak which appears in the drivers footwell next to the door in the channel that houses all the cables.
I have reduced the size of the leak by sealing the joints around the catchment space below the windshield (looks like it had leaked from new from there) sealed rubber grommets in the floor,fitted new door seal ,wax oil sealed underneath where all the push fit connectors go through the floorpan to fix wiring loom and door entry plastic cover,also sealed around door hinges and where the wiring comes through to the door.
The leak has greatly reduced and only shows itself in heavy rain when driving.
Any ideas would be greatly appreciated.