If it's like the 6-cylinder engine, there is a trick.
The fan pulley has several small bolts, and some additional unused holes.
Look back behind those holes, at the metal housing, and you will see two raised ridges. you can stick a small rod between those ridges and directly into one of the holes in the pulley. This will lock the pulley. The rod should be about the diameter of a small screwdriver shaft, and just bend it to work.

DG