Mercury Forum - Mercury Enthusiasts Forums - identifying rear axle shaft

Hi all. I need some help identifying the part number for the left rear axle shaft on my 1974 mercury marquis brougham with a 9 inch rear axle. I need a new shaft on my left side, but the only information I can find on the shaft itself is the following number: 3A8 E, and then a ford logo (Hard to se on the picture, but that's what is says). I assume this is a part number, but nothing close to my axle shaft comes up if I type this number in on google. I would really like to know the right part number for my left shaft so i know I'm bying the right one. Any good recommendations on catalogs with parts and part numbers for ford and mercury cars form around 1974 is also appreciated. Thanks.
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