Just thought I would put a post on that might save the 5th gen owners some trouble later on.
I have been stripping the car down as I am working my way through a respray at the moment.
I have 2 doors I bought as replacements and my two original doors.
All 4 doors have corroded, ranging from not too bad to really bad in the same place.
Where the window frame meets the top of the door panel behind the wing mirror. If you lift the outer door seal at that spot right at the point it joins they have all gone. It can't be seen until you get the seal lifted so worth a quick look and get something on it if it has started.
Looking at the structure there it wouldn't take too long to go right through the frame.
Being as all four doors have suffered from the same thing on doors from a 99 and 2000 I thought a post might be helpful.

