I don't understand the emphasis on mustang... You saying no mustang can be collectible? Not the mention the age part... Are new mustangs the most valuable? hahaman its a 10+ year old MUSTANG that fetches 20-30k. If that's not a collector car....
If history repeats itself, How much is a low production run of the top model fastback going for? Sure, the future may not end up the same but they are definitely no MS6 HAHA