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The 1982 oil tank is the last year tank with a drain plug. Future year tanks had a drain hose plugged off elsewhere.
It had a different, 2-piece chain guard so you could remove the front part to get at the drain plug. ¹⁾
Starting in 82, the starter relay was attached to the rear of the oil tank with a #10-24 x 3/8“ hex head screw and star washer.

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