the upright pin you have is for locking the tyre on, can't remember what goes on that.
but you need the two big bolts and lugs which go in the two screw in holes you have in your bonnet, these hold the tyre on.
haven't got a pic of it i am afraid.
just having the bolts and lugs will hold the typre in place, the earlier mountings didn't have the locking pin.