I stored some kits in an out building for a year. I believe older kits will be fine but the newer kits will warp over time in high heat. I would get tires and decals out. Jonathan has a good point also on the tires and decals.
Did the body pinch try to hold the interior back? I had trouble with a coronet like that and had to do some sanding on the inside of the body near the rear wheels...