Hi guys,
I am from Europe, Hungary, so English is not my native tounge, so bear with me, please!

I have stumbled upon this great site and forums when surfing the net for Mercedes parts a while ago! I have to say this site is awesome! The great expertise and wisdom contained here, and in the DIYs, allowed me - a hopeless guy when it comes to mechanical skill - to do repairs myself I would never imagined before that I am capable of! And I gotta tell you, it has given me a great deal of satisfaction (for being able to do it and for saving a lot of money)! So thank you to all the guys running this great site and all the ones contributing!

Enough of this rambling, I get to the point:

I've recently acquired a US spec 1987 W124 300D Turbo.
The engine and the transmission are flawless, but the rest is bust. Both interior and exterior. I already repaired a lot of stuff, but I got to a point when I have to ask, as I haven't found anything concerning this specific problem.

Majority of the air/AC/heat vents are not working! The heat and AC itself both run, but only the winshield and the driver's side vents are functioning! The double one in the middle, the passenger side one, and both of the lower, leg vents are non-functional, no matter how i set the controls!

Could you give me advice about what could cause this and how to repair, and how long should this project take to carry out? I guess I would have to remove the dashboard (my problems start here…) and the middle console to start with, and no idea what else...

Thank you in advance, your help will be appreciated!!!