Sidebar , the hood should handle the tyre OK , with good hinge inserts , and the lock pin holding the front down well on the support pads its should not move. Later defender hoods are not as strong , and the ali is thinner , so what happens if the vehicle is used on corrugated tracks is the flexing causes some splits to appear . There is a reinforcing kit supplied with the spare wheel carrier kit , but they were not always fitted by the owners . I have a 86 110csw (thicker gage ali) and that has carried a spare (mostly 235/85r16 BFG MT ) for all its life , including 12yrs in OZ , without any signs of a problem . HTSH .