1957 Dual Ghia, once ex-Frank Sinatra or Ava Gardner

I have seen this black one owned by Ir. Thaler in California many times. it has an updated Chrysler drivetrain. But is otherwise perfect. But the only picture I could find of Frank Sinatra with a Dual Ghia is a light colored one (you can't tell color because it is black & white picture).

That picture found here: http://www.curbsideclassic.com/automotive-histories/automotive-history-the-cars-of-frank-sinatra/

But I couldn't find Ava Gardner's pic with her Dual Ghia but though they divorced in'57 so it seems not the time to buy her an expensive foreign car (though he could have been buying it to win her back).

I am not a big fan of buying a car just because it was owned by a celebrity but have to admit that the "Steve McQueen" effect worked well for a couple Ferrari owners who got anywhere from 10-30% more for their cars at auction because their car could be tied to McQueen ownershio.

Anyway I would like to hear opinions on how one can prove celebrity ownership, and also an opinion on how much, percentage wise, the car would be worth if it had the original engine and trans? In the Ferrari world where SN of engine tied in to chassis SN I could see that of vital importance but isn't a '57 Chrysler V8 and two speed automatic trans easy to get for this era, and who would know what the engine SN should be?

Thanks for any comments,