To clarify: The problem is that once the mechanism is close to its proper location, you have to somehow feed the rod (about 3 mm diameter, and threaded at the top end to accept the black plastic pull knob) up through the hole in the door frame near the back of the window. There is not enough space for my thick hands to get in there, and it proved too difficult to try to get it using the hit-or-miss technique.
So, I found a brilliant solution:
A new tool is necessary, but is easily obtained: A plastic drinking straw.
Take the straw and feed it down through the hole, careful not to let it completely fall through. With it hanging down into the door inner space about 15 cm, it is not hard to feed the rod into the end of the straw. Once that is accomplished, move the lock mechanism into place, and the straw acts as a guide for the rod, and it goes right up through the hole. Yay!
I don't know how the original factory installers did it, but this worked like a charm.
