603 water jacket plugs - torque spec?
 

I'm slowly putting my ex-Sixto #20 head back together, getting ready to install it in my '87 300D Turbo (W124, OM603). The head has a fresh valve job and is all shiny and ready up go.

In the water jacket on the left side of the head are three plugs and two adapters. They all are aluminum, have aluminum crush washers, and screw into the aluminum head. However, I cannot find a torque spec for these things and don't want to strip them. Anyone know where I might find the torque values? Neither the FSM nor the Technical Data manual have this info.

Jeremy