Previa heating system troubles

[octane98]

Hi folks !

Lars from Denmark, Europe here !
Just bought a 1992 Previa. Love the car but are having a bit of heating-system trouble.
Wonder if someone might be able to help me.

I'm getting VERY little hot air into the cabin.
The temperature of the air is just fine ( as in hot )
but I just get VERY little of it no matter what I do.

..the blower ( under the hood ) works just fine

IMG_7967.jpg

..took the central/lower dashboard apart and checked the
various control-cables and mechanisms . Couldn't find nothing wrong
( and they all seam to work for adjusting and getting the heat to the screen / to the floor etc. )

IMG_7968.jpg

It's as if there is some restriction / blockage of the airflow somewhere
or maybe something has come loose, so the flow is almost lost somewhere between
the blower and the cabin-outlets.

I do have a Haynes manual, but can't find an overall view/schematic for the complete
heating system .
I did check these drawings from the 'Previa Collision Catalog' provided here on the forum,
but have a hard time figuring out where the problem might be

v1.jpg

v2.jpg

v3.jpg

Any help, guidance or hint would be greatly appreciated.
It's getting freaking cold up here.

Thanks in advance !