I'm not complete help, but I just put my 50 back together. I however have auto hubs, and I tightened my single nut to 50 and backed off 1/4 turn, then tightened a hair more. My directions say to tighten to 16 inch pounds, that aint much and I have no wrench like that so I tightened a hair after backing off 1/4 turn.
From what I came up with on this link you are right on the locknut.
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