I looked at 65 Formula S on Saturday. He’s owned the car since the late 60’s. Given it was his daily driver he had to contend with the high temps here in Phoenix. He replaced th solid fan with a clutch setup. The fan is a short diameter to fit the steel OE shroud and the clutch has a significant short shaft.
I did the research and here are the part numbers
Derele Fan. 17117
Hayden Clutch. 2947
