Managed to get 10 minutes in the dry and light this afternoon to have a look at this. I removed the interior door panel - pretty easy. There is one bolt behind the interior opening lever arm, 2 hidden under the rubber just behind the electric window switch which when removed reveals another 2 bolts attached to the door. There is also 3 screws along the bottom of the door panel that need removed. It is then just a cast of running a screwdriver down the sides to pop out the retaining clips - i think 3 on each side.
When i got the panel off and ran my finger along the bottom what i presume was the remnants of the rubber seal flaked off.
Is the solution to run a bead of silicone along the edge of the interior trim and reaffix?
If so i will be giving a go tomorrow afternoon if the weather stays dry.
Thanks guys - i am beginning to see the light through hopefully a watertight car.