I'm not sure how much more we'll ever hear about it. As I understand it, there have been fictitious claims in the past of it's discovery. This may turn out to be another. I picture a scene similar to the one where Geraldo claimed to have found Capone's secret vault.
From the accident photo the car doesn't appear to have been much of a candidate for rebuilding 'back in the day'. I figure that it was likely stolen for parts and then destroyed or taken by someone wealthy enough to have hidden it away in some private collection.
With the talk of million dollar rewards for it's recovery I imagine there are people out there willing to make forgeries. Hearing that Barris knows secret details to distinguish the real car from a fake, the person claiming to know the whereabouts of this particular car may back down from revealing more info if it is a fake. If it is the real deal, they may never reveal it's location if they don't think they'll get a reward. I wonder if the courts could make them talk. - After all, it is a stolen vehicle.