I'm sure all 3 will need pistons considering their age and compression. The one I have one the stand was the one I thought would have the best chance of being usable because it was running and it was only supposed to have 2,000 miles on it. I'm sure it only had 2,000 miles on it 50,000 or 100,000 miles ago. With the market in the condition it's in what's a complete carb to oil pan 67 440 worth ?