Torque specifications for Circuit Boards

[JOHN12]

Do anyone have a general torque reference guide for mounting circuit boards, mother boards, basically multi-layer PCB's?

i.e. A chart with application specific data

6-32 UNC - mounting a circuit board to a PEM

4-40 UNC Jack screw - mounting a PC back Panel to a
motherboard connector.

I'm trying to institute a general torque spec for my company and am having trouble finding anything published.

Thank's
John
Mechanical Engineer