A couple of weeks ago I changed the rear doors from a 80 series for a friend and I was amazed at the bad condition it was in. The bottom was totally rusted. We changed both rear doors we had a source for very good second hand ones.
On my 100 series the rear window motors struggled on both sides to close the windows and it was time to check if the guides blocked up and need to be cleaned and lubricated. As I had to remove the door cards it was a perfect time to check how the doors locked on the bottom. I was very surprised to see hardly any rust but I still would like to treat the area with some kind of rust converter and wax oil. For the time I will leave the door cards off to let it dry out and get some stuff for the treatment.