The guy probably found the thread. Who knows what drove him to look, though. Googling the buyer's name, perhaps?

We should make a policy to hide threads when the connection is made between owner and thief. ie: 48 hours after this thread started, and as soon as the stripped car guy identified the parts as his. Further communication could be done by PM between the victim and the people who provided info in the thread.

It's harsh, but I'd hate to see any more excelent examples of community detective work go unresolved. Maybe the cops and eBay still have a leg to stand on. Possession of stolen goods, etc.