Mark and Simon, thanks for your help---yes, the later style fan and blade are much easier to find, and used for a very long time (eg, used on the oil cooler for Ferrari 400i). Yes, the earlier cars used the bracket made of all-thread rod...very glamorous
. The picture I showed is from 8ma1046, a very original car. The other picture below (neatly plated) is '936, I think.