[njsteve]

Tires are really only safe to drive on for 7 years. Since they are the originals, I would take those off and store them somewhere where they won't be near any electrical equipment. Yeah, I know that sounds bizarre but the trace amounts of ozone created by electrical motors, like the one in your furnace accelerate the deterioration of rubber.

I have two original set of zero mile Michelin MXX tires and rims from my '93 Viper stacked up, hibernating in a closet.