Thanks for your suggestion. Although the car is approaching 20 years old, it spent the first 12 or so in California, and is remarkably rust and corrosion free (you should see inside the brake drums!). I'm beginning to think that I have a broken or breaking lever arm shaft, which I will investigate tomorrow. I found this on an old thread on the alfabb.com site and unfortunately for me it is looking just like my problem..... These links are copied over, just in case anyone else is having similar problems:
Replacing the Alfa Clutch Pedal Shaft
http://home.hiwaay.net/~ortak/Clutch...pivot_arms.htm
If anyone has other suggestions, please post them here.