Hey there timmyboy. First off, the Inno Racks INA744 BoardLocker surfboard rack will work on your Toyota FJ Cruiser factory roof rack. The problem is the INA744 BoardLocker has a width restriction of 24 inches. At 29 inches your SUP stand up paddle board is too wide for this carrier. For SUP stand up paddle boards I definitely recommend going with the
Inno INA444 Locker instead. No width restriction and includes factory rack compatible foam pads and integrated lock system. You can set this SUP paddleboard rack to any width on your Toyota FJ Cruiser roof rack crossbars. Another option is the
Inno INA745 Crane Board Carrier for transporting a SUP. However, the Inno INA745 does not include crossbar pads, and rack pads made for factory racks are very hard to come by (anyone know of any good models out there?). If you have a SUP bag to put the board in then you'd be all set to use this carrier though.