klobbr

Saw this on my decoded VIN, and what I can tell its a red light on my dash, a sticker on the windows, and the vin etched in the glass. There is a cute little triple chirp when I stop the car and pull the key out of the ignition too.

What I don't understand is what this alarm actually does? Ignition kill? Motion? Anti tow?

(BTW, I finally sounded the horn just to see if that's what the alarm would sound like after owning the car for a week. That is a nice harmony.)

Floobydust

Anti-theft, option 551, was standard equipment on the Cabriolet. The system is simple intrusion/radio theft that sounds a horn and flashes the lights if triggered. It interfaces with the power door lock circuit and various door switches to arm/disarm automatically.

I don't believe the chirp you describe is factory. Has someone fitted an aftermarket alarm/keyless entry? Starter disable alarms were often part of the "dealer fleece package" back in the day, even if the car came with a factory alarm.

klobbr

Probably some thing extra as you suggest.
There is a non factory looking bulb in the dash.