It is important to know that tables PROJ and PRPS with fields like PSPNR/POSID/PSPHI all have Conversion Routines associated with them to convert the values to internal SAP format and vice-versa.
To find out these Conversion Routines, go to the domains of the respective field and check under Convers.Routine.
The Conv Routines are different for different fields, so it usually requires a little bit of "playing around" to get it right.
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