Looks to be aftermarket left hand axle, by the 'L' stamped in the end. I understood OEM's were stamped 'S' or 'D' for 'Sinistra' or 'Destra' (Italian left or right).
The axle nut is a cinch nut, which is designed to be a single use item.
Also renew that chamfered thrust washer on the axle. The axles were rebuilt on one of my cars and the thrust washers not replaced; I had to rebuild them again within a couple thousand miles.
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