Does replacing the headliner on a 1969 Mercedes 280SL require removal of the windows? And what type of padding is required for replacement?
Replacing the headliner is not a quick and easy task. All the windows and most of the chrome as well as handles ….has to come of. The foam due to its age is brittle and falling apart but easy to get and replace. I believe its 8 and 5mm in thickness which you can get in multiple places. Personally, unless you are planning to restore the hardtop, I would try to save and clean what you have. If you search the forum, look for the hardtop restauration posts and guides, these will explain the liner change as well.
BTW, welcome to the group.