Power automatic seatbelts were only on U.S. spec cars. It was part of the passive restraint rule if you didn't want to fit the vehicle with airbags at that time.
It's very possible the wires on the isc servo are no longer making good contact and causing issues. There used to be a how-to on re-soldering the wires on the isc servo.
I have also had the CXRacing rad for a few years now and I'm using their fans and shroud, and they fit fine with no issues. However, I also had to slightly enlarge the mounting bracket holes a little bit, no big deal.