4K door locks

[Andrei Kogan]

Dear list,
I am looking for ideas on how to fix  three doors in my 4k. They all have
the same problem -- when I pull the lever inside, instead of opening, the
mechanism pulls the locking knob down and stays closed. It takes several
tries  using both hands to get the doors to open. It appears that the ( 19
yo)  springs inside the lock assembly lost some strength, and the little
"catch" in the bottom of the lock does not come down enough for the lock to
release ( I experimented some with a screwdriver on an open door). Has
anyone tried rebuilding these, replacing the springs  etc? or the only way
to go is getting a replacement ( assuming it's even available, the car is
an 84)

A related question. The section on interior trimin Bentley does not discuss
cars with power windows. To get the trim off the rear door, it seems that
one needs to unsolder the wires from the window switch. Is this true or am
I missing some obvious way to take the switch apart?

Many thanks! I am hoping to get   a few more years out of her , and greatly
appreciate your help.

Andrei