N.Z.S.Co ships were always registered at Plymouth. Not sure about the MANAPOURI class when built in the new Federal colours.
Some early two funneled P&O liners were registered at place of build, i.e. Belfast.
I remember seeing this ship when she was berthed in the KGV dock in London during the early 1950's; I am fairly certain that like the P & O liners "Mooltan" and "Maloja", she embarked her passengers there, she seemed to berth at the north side of the dock where I believe the runway for the airport is; a sad reflection on what things used be like before the airlines killed it off.