Service manual for my '06 ElectraX (paraphrased) in Section 3 Page 3-26 says to:
1. Loosen the fork pinch bolts,
2. Loosen the Set screw under the stem nut,
3. Tighten the Stem Nut,
4. Assembly the reverse of the same.
I noted my manual does not give a torque value for the Stem Nut.
That's how I did mine a few years ago. I torqued to 55, backed off, retorqued to 15.
Seems to be fine.
If I ever do it again I'll have to get my 18" breaker bar back. I gave it to a friend. I did keep the socket however. I've given a lot of stuff away to friends so it doesn't get shit-canned when I die.