94-96 Cluster Mod?

I came across this picture of a somewhat different 95 9C1 Instrument Cluster the other day...



I don't recall having seen this before, and if I remember correctly, this picture was taken many years ago. Anybody know how this is done? I checked one of my spare clusters, and the symbols are there, the printed circuits too, just the bulbs and sockets are missing. I do understand what it would take to hook those lights up - I just don't know if some or all of the neccessary wiring connections might be in place already. Probably the case for Door Open, certainly the case for Gate Ajar on the Wagons, but the Hazard Triangle has got me puzzled. Never saw this activated anywhere, not on any Impala, 9C1, Civilian or Export. Still, the lens and circuit are there.
There's even one more unused slot that has a different Brake Symbol.

I'm gonna put some bulbs in and then see what happens, but if anyone has the deatails on the why & how, or has seen/done this before let me know.

On my '74, there is actually a Door Ajar lamp that as far as I know, was never used on any 71-76 Chevrolet, my cluster was used from 71-74 and there was a slightly altered one for the last 2 years. I was going to try and run a wire from the door switches just for fun, but with the doors being as big as they are and there only being 2 of them...I think I'd notice if one was open.

The door open will work if you just add the bulb.

Is the triangle there to let you know you have your hazards on while driving? Like say you put them on and drove "x" amount of miles would it illuminate to remind you? Like the blinker chime?
How about if you have a light out and turn on the hazards?
Or if the hazard flasher is broken? (it's separate from the blinker one)
Now I'm gonna go nuts till I find this out!

Well, from a European point of view, that Triangle should simply do what the two green arrows do on any Caprice already - flash while the hazards are on. With the exception that the Triangle should keep flashing even with the ignition off. That's the way it is required by law, Hazard Control Lamp has to be RED, shaped like a Triangle or marked with one, and needs to stay on with ignition off.

That's what I think it SHOULD do. I do not know what it REALLY does (nothing obviously so far with the bulb not installed), or why they put it there in the first place.

Ok. Just putting in a bulb does NOT activate the Triangle. I've tried. And yes, the bulb I used was known good.