1965 Formula S w/AC: What is Factory Correct Fan?

Regarding the the fan/clutch assembly I uploaded in post #3, my curiosity drove me to clean up and remove the '65 AC fan clutch and look for part numbers. I found the factory DPCD stamp on the fan blade, and the factory part number on the fan clutch. It matches the '65 parts book as the only AC fan clutch offered for V8 A bodies in '65, part number 2536675. So this is a correct '65 assembly for V8 AC cars with a fan clutch, but leaves open the possibility that some factory AC cars didn't use a clutch, and therefore used a different fan because this fan must be used with a clutch due to the larger diameter hole. 1965 was the first year for factory AC in A bodies, so there could have been several approaches, and/or mid years changes.