Classic Object Pascal for free
Following on from Alcatiz's suggestion, I tried to implement the call in a unit - but ran into various problems trying to define a function as 'External' .. within the unit. In short it was a no go.
However, it turns out the desired (Windows) function "SHFileOperation" is already available in the VP Unit
ShellAPI .. and so doesn't need to be defined (as an external), seperately.
Thus, as long as the setup stuff is done (as illustrated in Alcatiz's program), the call to SHFileOperation
(via ShellAPI) works just fine and can be successfully incorporated into a unit as well!