Re: NF 5.5X22 Mount ?
No loc-tite on the rings, lap them properly and you will be good to go. They should come with torque specs from NF, usually around 65in-lbs. Careful not to over tighten.
For leveling the cross hairs my method is to hang my carpenters square on the side of my shop using a level to insure it is perfectly level on both planes. Then I align my cross hairs both vertically and horizontally, easy money.
"I'm interested in rifles, but only accurate rifles are interesting". Col. Townsend Whelen