PCC prior to XA Rel 6 Actual Cost

MAPICS Listers,

PRior to XA Rel 6, MAPICS Payroll was required for PCC to do actual cost.
Now you can just have the EMPMAS file out there and DFU the rates, etc.
Working from memory (fuzzy at best) we believe actual cost used to consist
of  ((Employee rate + Shift differential) * hours)   -    (because you had
to have Payroll).  We are not talking about overtime formulas, just the
straight-time cost charged to an operation when tailored for actual cost.
Can anyone out there test this for us?  Reaching waaay back, I am (almost)
positive it worked this way at DB Mod 4.

The PCC manual states:
EMPLOYEE RATE OVERRIDE (ERATE) If an employee number was entered and the
employee's hourly rate is not used to determine costs, type in an override
hourly rate.  This is valid only for run codes S and R.
EMPLOYEE SHIFT OVERRIDE (SHIFT).  This is valid only for run codes S and R.
If an employee number was entered and the employee's normal shift is not
used to DETERMINE COSTS, enter an override shift.

How could shift be used to determine costs unless the differential is added
in?

TIA,
Ann Neal