spin on , torque, and headspace with a pull-through reamer .
We built a "Special" at the CMP Maintenance Course.
The barrel went on easy to the last 1/4 turn, then it was a crank to get the witness marks aligned.
So, what you have above is all we did - though it was a hard last 1/4 turn.
We had 20 people in the class, and I don't recall any barrels needing a should turned, but I do recall that we all commented on the leverage needed to seat the barrel.