Then look it up and see what it goes with.
Certainly matches the '64 .
The codes for VC1 etc are probably in the begining
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Still used in '65 with A/C
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Doesn't seem to be in 1966 but maybe I missed it.
The 1966 FSM has one of these charts in the Service manual.
Maybe its in 65 or 64 or in supplement or Tech bulletin
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Just looking at the A/C optioned engines, they got 7 blade fans, so no help there.
But the 6 blade fan shown also uses a 2" spacer. Now you can check the spacer p/n for 64 and 66 to see if they are the same.
Also we can figure out which water pump and pulley ratio these fans worked with.
It looks like only the thermal and viscous drive fans get the small impeller water pump and the faster pulley ratio.