It occured to me that perhaps there was an alarm that I could not find. I believe I know where the module would be, though, and that space is empty - with unused mounting holes. I also tried 'triggering' the alarm by locking the car with a window open, and reaching in to unlock and open it - nothing. I looked for a hood pin switch - none found, and there is no trigger wire on the trunk lid switch.
I don't know which zones would be monitored with a factory alarm, and my Haynes manual ('84-'88, marginally useful) doesn't show one. My Owner's Manual does, but also mentions lots of stuff the car doesn't have. I presume it was a popular option that the previous owner did not order, or was only available on the 2.6l?
Thing is, if it were an option on this model, I would expect a wiring harness for it. This is something cheap and easy to add on the production line, but would be an unecessary hassle for a dealer to wire up - cutting his profits. So, I'm hoping it's there - anyone know?