Thank you all for your answers!
I will include some photos. About a month ago I replaced all the wires (hell of a job

) but all the wiring is correct. What we did do is to try and change the wires on the regulator like they originally were. (see picture) still no charging.
The altenator has two contact points on the top and one big on the back. If you look from the front of the car the two contact points are on 9 o'clock. The altenator itself sits on 5 o'clock of the engine (if you look from the front)
I opened it up to see if anything is damaged.nothing

. Cleaned it up and put it back on. Still no sign of life.
We are going to bring it to someone who will rebuild it. But maybe somebody knows already what's wrong (like the position or wiring).
All help is much appreciated.
With kind regards,
Thijs