Ok,
These are a molded rubber piece that are attached from underneath. You can still purchase these as aftermarket replacements at various locations (can be called "scrapelist" in Dutch catalogues). I have some arriving soon for my 145.
Removal: Remove the aluminium window surround and the window glass. Reach up inside the door and pull the remnants off the door lip or push it off from the top. You may find rust in this area so it is a good idea to be prepared to treat it properly and repaint with several coats of a good enamel paint on both sides of the mounting lip.
Installation: I've not done this yet, however I'm expecting that some rubber grease and some strong cord may be required to assist to get the rubber lip to sit on top of the door. Basically it mounts from underneath via a molded clamping strip similar to what covers the door seams. You may find it easier to remove the winding mechanism from the door cavity. Once done, reassemble the door components. I'm going to be installing additional sound deadening while I've got good access.