Even wat research gedaan en dit stukje info gevonden van iemand uit Rusland:
Hi guys & gals.
Just wanted to put some information about non standard air condition control systems. I'm not sure how or if the apply to Vauxhall (since I'm in Serbia, I drive Opel Calibra).
There are 2 types of non-standard factory-fitted AC control systems
1) Digital (made by Opel, originally made for Vectra A (Cavalier mk3), but was installed in callibra upon special customer requests)
http://img99.imageshack.us/img99/4415/copyofdsc000063kp.jpg" onclick="window.open(this.href);return false;
2) Automatic (made by some Italian company (can't find the name right now). They built only 50 control systems ever, so yeah, they are quite rare).
http://img122.imageshack.us/img122/635/76484243042006calibra6p8bs.jpg" onclick="window.open(this.href);return false;
However, both systems share the same airflow box (behind the front panel) and the only difference from the standard airflow (with or without AC) box is that these boxes have small electric motors controlling the airflow inside the box instead of mechanical air ramps used in standard ventilation boxes.
Also, the only difference between digital and automatic is that automatic AC control system has a built-in temperature sensor so you can basically set the desired temperature and it will shut down when the target is reached and engaged again when the temperature rises a few degrees from the target.... and yeah, the Italian control system is much more nicer than Opel's.
I'm also a fan of digital gizmos in cars and I intend to make a digital AC control unit for my Cally (already got the ventilation box with el. motors), so I'll keep you posted on the progress.