There is some history with collectible Fords and "special paint". In 1968 many of the Shelby/Ford dealers were "stuck" with excess inventory. The dealers were getting 5% rebates because Shelby's were a whopping $4,000+ back then and considered expensive. Ford started a "special paint" promo to boost sales for mustangs and Shelby's (GT350's and GT500KR's). There was Orange, Yellow, Green, and Red. I own one of the yellow ones, Jimmy Connors bought it for his 1977 Playmate wife Patti McGuire. I'm still trying to get the backseat to talk, no luck yet....
The cars do trade at a premium, yellow ones 10-20% the others it's hard to say because they have not changed hands in recent times and they are more rare. I hope Sonic Blue fetches something descent... I did sell one of the yellow GT500kr fastbacks for $181k in 2010 before buying my current convertible. It won concours gold and was a nice car, prices for that same car non-special paint are about $125-135k. Some similarities but Sonic Blue seems to be a 1 of 1 for any special paint GT, should do very very well especially if someone in Saudi Arabia or Kuwait wants it
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