3rd row are specific.
I might be wrong, but I think the end plate and the retracter are mounted higher up on the 3rd row relative to the second row, so even if you could fit them, the belt will be very slack and not retract fully. However, you would not be able to fit the roof extender bar easily. LWB 3rd row might be different again due to location of wheel arch relative to seat position, and therefore the mounting height for hardware.