Our spare wheel/tire is mounted on the front wall of the deep cargo bay. A PITA to remove stuff and get access to remove the spare which is heavy. I would have the emergency service guy wrestle it out, remove bad wheel/tire and install spare when needed. It is good/prudent to replace tires when serious side wall cracks appear or when tires are older than 5-6 years old by date codes. Why risk a hassle to get a replacement tire in the middle of nowhere. BTW, If you hear/feel an unusual bumping underway, stop and inspect for bulges in tires and danger of tires coming apart/blowing and damaging under-parts of your rig with possible loss of control.