Mopar RV2 A/C clutch

[Airmail440]

Replacing the ac clutch on my 74 Charger, so I order what is supposed to be a correct replacement, the pictures def. looked the same on ALL the Ebay listings. the one I got has no slot for the key on the compressor shaft even though pictures show it and it's correct #. After researching various nos (3846523) and Four Seasons 47834 which I got but all pictures show the slot and some nos don't have it?? Is it necessary? Is new replacement a more pressed on fit?

[John_Kunkel]

Tapers are used in a lot of shaft installations with and without keys. The taper on the compressor shaft probably has enough gripping ability by itself for most operating conditions but under severe load I'd want the key...the factory thought it was necessary.