Just be aware that water will run down the inside of the membrane and leak out or pool between the door and the membrane. There are supposed to be deflect shields inside the door above the apertures, you may well have these fitted but very rarely are
The use of these door membranes has always mystified me somewhat. Obviously they are not there to protect the door, so therefore I had always assumed they were there to protect the inner face of the door card and its leather covering.
If that's the case, why did they never simply put the membrane on the inner face of the door card rather than on the door? Or is there another purpose that I'm not familiar with?
On the cars that I've owned in the past (admittedly none of them top-rank stuff like this E Type) whenever I've had to get to the window winder mechanism or whatever I've removed the membrane and waterproofed the inside of the door card instead with no apparent ill-effects. Not suggesting that this should be done in a proper restoration, just interested in the original logic of using the membrane.
