Dear Lord Vader,
Thanks for your reply, I really appreciate the effort you made. I can confirm that my car is definitely a E30, even though the model year is 1993. It was purchased by the original owners at the end of 1992. The U.S. (I moved here recently from Ireland) is funny like that, you could buy a car at the end of a calendar year but it is sold as the next year model as they seem to do some upgrades towards the last quarter of the calendar and advertise as the next years model.
1992 was the last year they produced the E30 cabriolet (it is actually the E30 cab model with the electric roof) - but the manufacturers claim it is a '1993' model.
Not sure if you are au fait with this model as you are with the E36?, hopefully you are as your insight is incredible.
thanks so much,