Correct, the 95 and 96 pistons carry different part numbers. These are the standard piston assemblies available for the 96 engine:
1996 4798329, 6, "B" Size, 3.8742 4798330, 6, "C" Size, 3.8746 4798331, 6, "D" Size, 3,8750 4798332, 6, "E" Size, 3.8754 4798333, 6, "F" Size, 3.8758
The rods are all the same.