There have been instances of tyres exploding in sunlight or vehicles kept inside. Tyre pressures have been known to nearly double on sunny days on vehicles kept behind glass. Tyre management does not stop even if the vehicle rarely moves. A good coat of tyre black does help, or other propriety products. For safety blocking the vehicle up either with axle stands or wood blocks is prudent. Keep a tyre foot print on the ground for vehicle stability but reduce the air pressure in the tyre. Turning the tyres periodically will help to stop sidewall cracking. On a flat bottom vehicle look inside of the hull for any ribs or strength braces and work with the hull, spread the load.