I haven’t been in that many Sprinter vans but it seems as though most of them have broken heater vents. Yesterday I got some used replacement vents from a wrecked sprinter van that weren’t perfect but much better than my vents. I’ll install them later when I get some of the more major things done, if I did it now it would sort of be like putting frosting on a cake before you make the cake. Here is a youtube video describing the removal process of the passenger vents.