Mercedes 190 2.3 16v - ASD valve connections
 

I am restoring the SLS and am having a problem identifying the hydraulic line ports on the ASD valve. I have the schematic for the system and a cross section drawing of the valve but unfortunately there are no markings on the valve body to identify the individual lines. I am assuming the single largest diameter port is for the return line to the reservoir. Seems to be v.few photos on this so any help greatly appreciated.