Blind headlight: Change cover (polycarbonate separately)?

There are many threads and YouTubes on the topic of blind headlights, but at a certain age / degree of destruction this is no longer enough. It is about a Jazz Bj 2003, whose headlights have been polished a few times. Now the TÜV has painted. According to research, the covers are sold separately for jazz, of course much cheaper than completely new headlights. Does anyone have experience here in the forum with these parts:https://www.amazon.de/…/B0BHVRKJNT How difficult is it to replace the glasses? Do the headlights also have to be completely dismantled? How long does it last? Will it be waterproof again?