Interesting Fact: My 68 RSSS 396/325 Auto (build date 11/67) with AC came with a four blade fan unless the original owner switched it out. I know the report says that it should be a five blade fan with clutch. I'm 99.9% sure my setup is original though. Car only has 52000 miles and I have all of the orignal engine components (water pump, alternator, and starter) which I had rebuilt. The fan spacer was still attached to the water pump when I bought the car. Car also has the 4-core Harrison radiator.