Speaking of odd 427/425 cars, there were two that used to show up at Osceola. One was a dark blue 66 Bel Air 4-speed wagon owned by a guy named Bob Fox. He owned a service station and ran it with headers and slicks at first. When NHRA put a pure stock section in the rule book, he went back to manifolds, mufflers and Prowler GT street tires. Dont know how fast he could really go cause he just went fast enough to win. He never let it all hang out. The car was for sale in the late 70's for $3500 cause he was retiring and moving to Arizona.
Second 427/425 car was a special ordered puke green 68 Bel Air 2 door post car with an in dash factory tach and
three on the tree 
owned by a guy named Steinbruner. According to his brother, he wanted to pay cash for the car and was too cheap to spend the extra bucks for the 4-speed. After he quit racing the car he used it as his daily driver till the 74
gas crisis. He pulled the 4-2-7 out and swaped it off for a small block to save on gas money. The car is still around the area and I see it at the drag strip maybe once a year. It's primer grey, still has a small block..... and it ain't fer sale.