Driver's door has never had lock tumblers, and I found the link rod and latch arm hanging inside the door, still attached to the door latch mechanism.
Installed the new tumblers, return spring, and retaining 'washer' (silver, with tang, seen below) in the door handle, BUT the latch arm (gold-anodized, seen below) only fits in THIS orientation, due to it's tang.
Impossible,...won't fit in the door, and the shop manual shows it oriented toward the front of the car,...

Any idea of how these lock/latch parts go together properly? Perhaps it's the wrong arm,...
I have not pulled my passenger door apart to check what's in there,...but it has tumblers, and may still be assembled,...
Thank you, Todd.

GAD!
Thought that I'd looked this over extensively last night. Must have had too much beer!
Solution is SIMPLE!!! What an idiot I am,...and in too much of a hurry, this morning, to get everyone's ideas!
Invert the tumblers.
I guess I still hope this helps someone,...! Todd.

Just a mention about the quite interesting window regulating system that is inside our doors! Cables, how cool!

Drivers side window suddenly wouldn't go down, seemed like something was binding.
Pushing on the top of the window while cranking suddenly freed it up and now it goes up and down easily (especially after spraying some silicone down the felt guides )

I had to lube my felt guides also (along with everything else while I was there!),...worked good!
Glad you got your window back to functioning, Paul. Especially driver's side!

PaulC wrote:Drivers side window suddenly wouldn't go down, seemed like something was binding.
Pushing on the top of the window while cranking suddenly freed it up and now it goes up and down easily (especially after spraying some silicone down the felt guides )

Sometimes they hang up on the bar going from the inner door handle to the door latch mechanism. The bar can bend out if the handle is pressed down too hard to lock the door from the inside and then it gets in the way of the window causing it to hang up.

The one on my drivers door was like that so after I straightened the bar I made a sheet steel guide to keep it tight against the inner skin of the door so it would be less likely to happen again.

OMG! Is THAT why Fiat placed a 'zip tie' around the bar, to secure it to the inner door metal,...?! Even referenced in the shop manual,...Mine were broken when I disassembled the doors, but I'll replace them next opportunity.
Just one small clear/whitish zip tie in each door,...