Well, I've seen someone removing vents but I think that is not my solution: I'm travelling enough to need all vents in summer and I don't want to modify too much the stock layout.
In my first post I was talking about adding a modelled box behind the vents: I can loose the clock (it's the only crappy component of this car) and I've a lot of space there, buy this mean building a VERY NICE fiberglass box, maybe my V2.
Egon
P.S. As for many things, the best is in the middle