Found the replacement rear wiper for the FX. Also found installation video. Its super-easy once you see it.

Rear Wiper: https://www.wipers123.com/product_display.php?make=Infiniti&makehid=Infiniti&year=2008&yearhid=2008&model=FX45&modelhid=FX45

xx-B wiper blade for Rock Loc 3 Rear Wiper Arms Install Video: https://www.wipers123.com/wiper_blade_installation_videos.php

Hope this helps others.