From what I read, very few of them were inside. Most were left outside to rot into the ground and are probably little more than junk.
From the photos at the auctioneer's site some of them look in restorable condition. But I can appreciate what happens to cars left outdoors. A number of years ago there was an auction of a similar old collection of cars in Massachusetts. Grown men nearly cried seeing close to a dozen 1950s Thunderbirds left to rust outside, along with over one hundred other vintage cars that would have easily restored if they were stored inside. Many were worthless due to rust by the time the collection was auctioned off.