I just bought a 91 Corolla from my mom and she has been the only owner of it since it was new. I have done several upgrades to it over the years for her as it was the base model. Only extra thing it may have had was the AM/FM with cassette. I put in a cup holder, a factory clock and an inside adjustable driver side mirror after the original was broken off from her hitting smoething.
Durring the installation of the clock and cup holder, I found that the coin holders on the dash had wire harnesses behind them for options not included in the car...such as cruise control. The clock just had a blank plate there but the car was wired for a clock. I just had to plug it in. I'm wondering... did Toyota put the componants in for Cruise Control but simply removed the feature by not putting in the controls (and a fuse presumabley)? The wire harness for cruise is there behind a coin holder. Can you simply go buy a cruise control panel from a junk yard, plug it in and have cruise control? Or is it also missing the actuator, speed sensor and park/neutral position switch?
Also, I'm wondering if the doors have the wiring present for power locks and windows. Of course the door panels themselves and such would need upgrading but if so, that would be something to consider if I wanted it.