Was happy to get my HOV lane decals for the Prius Plug-In.
Glad they included a diagram of where to install them because the written instructions were hopelessly poorly written.
To me, the right side of the bumper is on the right side of the vehicle. To California, the right side of the front bumper is on the left side of the vehicle (looking at it from the front, the driver's side is on the right).