you can NOT do this IFR.
Must be VFR in VMC.
Under the FAR the definition of PIC is:
*Required crewmember
*Sole manipulator of controls
*Responsible for the safe conduct of the flight
For a "P2" to log PIC (under FAR) he must be a required crewmember, this he can only be when serving as safety pilot in VMC as a "look-out pilot" while the sole-manipulator-of-controls flies with a view-limiting device.
You basically share the required functions so that one is manipulating and the other is responsible for safe conduct...
If you fly IFR the person NOT manipulating the controls becomes obsolete.
Additionally, I can mention that any employer in the US will look at this way of logging with a certain amount skepticism, even if it's legal under FAR I would seriously consider if it's worth putting in your logbook.
It's definitely not approved under JAR!