I guess there are some parts and pieces that are missing.
going from memory, you are missing a long eye-bolt piece, and a wing nut. but you're also missing the entire carrier, it is a T handle shaped piece, that pivots above the rear axle.
some pics in this wanted thread:
WTB: FJ 45 LWB Under box spare tire carrier
bolt pics in this thread:
Wanted - SPARE TIRE LOCKING BOLT