Maybe this will help ......

The link below is the section for the 2001 Xterra Service Manual dealing with the suspension system.

Save the file to your local hard drive (there is a "Save" link in the menu at top), then view it with your local PDF reader software.

You'll want to look at pages 12 and 13. On page 12 the torque values are listed in both Metric and English.

https://viewer.zoho.com/docs/nc3x8

The torque values might be only for the OEM shocks. You might want to doublecheck with Bilstien recommendations too.